Tm 11-6625-2910

Transcript

TM 11-6625-2910-14 TECHNICAL MANUAL OPERATOR’S, ORGANIZATION, DIRECT SUPPORT AND GENERAL SUPPORT MAINTENNCE MANUAL FPR SIGNAL GENERATOR AN/USM-47 (NSN 6625-00-445-6917) This copy is a reprint which includes current pages from Changes 1. HEADQUARTERS, DEPARTMENT OF THE ARMY OCTOBER 1978 WARNING DANGEROUS VLOTAGES EXIST IN THIS EQUIPMENT Voltages as high as -1250 volts exist inside the cabinet. Be careful when signal generator is removed from cabinet. DON’T TAKE CHANCES! TM 11-6625-2910-14 C1 HEADQUARTERS DEPARTMENT OF THE ARMY WASHINGTON, DC 23 November 1979 } CHANGE No. 1 Operator’s, Organizational, Direct Support, and General Support Maintenance Manual for SIGNAL GENERATOR AN/USM-47 (NSN 6625-00-445-6917) TM 11-6625-2910-14, 2 October 1978, is changed as follows: 1. New or changed material is indicated by a vertical bar in the margin of the page. 2. Remove and insert pages as indicated in the page list below: Remove Insert i and ii.............................................................i and ii 0-1 and 1-0 ....................................................O-1 and 1-0 A-1 .................................................................A-1(A-2 blank) B-1 and B-2 ...................................................B-1 and B-2 3. File this change sheet in the front of the publication for reference purposes. By Order of the Secretary of the Army: E. C. MEYER General, United States Army Chief of Staff’ Official: J. C. PENNINGTON Major General, United States Army The Adjutant General DISTRIBUTION: Active Army TSG (1) USAARENBD (1) USAINSCOM (2) TRADOC (2) DARCOM (1) TECOM (2) OS Maj Comd (2) HISA (Ft Monmouth) (21) USACC (2) Armies (1) Svc Colleges (1) USASIGS (10) Ft Richardson (CERCOM Ofc) (1) Ft Carson (5) Ft Gillem (10) WSMR (1) USAERDAA (1) USAERDAW (1) Army Dep (1) except LBAD (10 SAAD (30) TOAD (14) SHAD (3) USA Dep (1) Sig Sec USA Dep (1) Units org under fol TOE: 29-134 (1) 29-136 (1) 29-207 (2) 29-610 (2) 32-52 (1) 32-57 (1) NG: State AG (0); Units - (0) USAR: (0) For explanation of abbreviations used, see AR 310-50. This manual contains copyright material reproduced by permission of the Hewlett-Packard Company, Palo Alto, CA 94304. TM 11-6625-2910-14 TECHNICAL MANUAL NO. 11 - 6625 - 2910 -14 } HEADQUARTERS DEPARTMENT OF THE ARMY WASHINGTON, DC, 2 October 1978 OPERATOR’S, ORGANIZATIONAL, DIRECT SUPPORT, AND GENERAL SUPPORT MAINTENANCE MANUAL FOR SIGNAL GENERATOR AN/USM-47 (NSN 6625-00-445-6917) REPORTING OF ERRORS You can improve this manual by recommending improvements using DA Form 2028-2 located in the back of the manual. Simply tear out the self-addressed form, fill it out as shown on the sample, fold it where shown, and drop it in the mail. If there are no blank DA Forms 20282 in the back of your manual, use the standard DA Form 2028 (Recommended Changes to Publications and Blank Forms) and forward to the Commander, US Army Communications and Electronics Materiel Readiness Command, ATTN: DRSEL-ME-MQ, Fort Monmouth, NJ 07703. In either case a reply will be furnished direct to you. Page O. I. II. III. IV. INTRODUCTION ............................................................................................................................................... O -1 GENERAL INFORMATION ................................................................................................................................ 1-1 1-1. Description ........................................................................................................................................... 1-1 1-6. Accessories Furnished ........................................................................................................................ 1-2 1-8. Accessories Available .......................................................................................................................... 1-2 1-10. Instrument Identification ...................................................................................................................... 1-2 INSTALLATION .................................................................................................................................................. 2-1 2-1. Inspection ............................................................................................................................................ 2-1 2-4. Air Filter ............................................................................................................................................... 2-1 2-6. Power Requirements . ........................................................................................................................ 2-1 2-8. Power Cable ......................................................................................................................................... 2-1 2-11. 230-Volt Operation ............................................................................................................................... 2-1 2-13. Repackaging for Shipment .................................................................................................................. 2-1 OPERATING INSTRUCTIONS .......................................................................................................................... 3-1 3-1. Introduction .......................................................................................................................................... 3-1 3-3. Harmonics ............................................................................................................................................ 3-1 3-6. Operating Procedure ........................................................................................................................... 3-1 3-9. CW Output .................................................................................................................................... 3-1 3-10. Square-Wave Output ..................................................................................................................... 3-1 3-11. Internal Pulse Modulation ............................................................................................................. 3-1 3-12. External Pulse Modulation ............................................................................................................ 3-1 3-13. Internal FM at Line Frequency ...................................................................................................... 3-1 3-15. External FM .................................................................................................................................. 3-2 PRINCIPLES OF OPERATION .......................................................................................................................... 4-1 4-1. Introduction .......................................................................................................................................... 4-1 4-3. Pulse Section ....................................................................................................................................... 4-1 4-5. Input Amplifier and Pulse Rate Multivibrator ................................................................................. 4-1 4-10. Schmitt Trigger : ........................................................................................................................... 4-3 4-17. Sync Out Thyratron 43 .................................................................................................................. 4-3 4-19. Delay Multivibrator ........................................................................................................................ 4-3 4-27. Delayed Sync Out Thyratron ........................................................................................................ 4-4 4-29. Pulse Width Multivibrator .............................................................................................................. 4-4 Change 1 i TM 11-6625-2910-14 Model 626A Table of Contents Page SECTION V. VI. APPENDIX A. APPENDIX B. SECTION APPENDIX C. APPENDIX D. SECTION APPENDIX E. APPENDIX F. APPENDIX G. APPENDIX H. APPENDIX I. I. II. III. I. II. III. IV. 4-33. Modulator Section ................................................................................................................................ 4-5 4-36. RF Oscillator Section ........................................................................................................................... 4-6 4-38. Reflex Klystron Operation .................................................................................................................... 4-7 4-45. RF Oscillator Tube ............................................................................................................................... 4-7 4-50. Power-Monitor Section ......................................................................................................................... 4-9 4- 54. Output Attenuator Section ................................................................................................................... 4-10 MAINTENANCE ................................................................................................................................................ 5-1 5-1. Introduction .......................................................................................................................................... 5-1 5-3. Cleaning the Air Filter ......................................................................................................................... 5-1 5-5. Test Equipment .................................................................................................................................... 5-1 5-7. Troubleshooting ................................................................................................................................... 5-1 5-8. Locating Trouble ........................................................................................................................... 5-1 5-11. Troubleshooting Charts ................................................................................................................ 5-1 5-14. Power Supply ....................................................................................................................................... 5-1 5-22. Repair .................................................................................................................................................. 5-3 5-23. Cabinet Removal .......................................................................................................................... 5-3 5-25. Tube Replacement Chart .............................................................................................................. 5-3 5-27. Servicing Etched Circuit Boards ................................................................................................... 5-3 5-29. Klystron Tube Replacement ......................................................................................................... 5-5 5-36. Reflector Potentiometer Replacement .......................................................................................... 5-8 5-38. Replacing RT1 .............................................................................................................................. 5-10 5-40. Adjustments .......................................................................................................................................... 5-11 5-41. Zero Set Control Adjustment ........................................................................................................ 5-11 5-43. Schmitt Trigger Level Adjustment ................................................................................................. 5-11 5-45. Adjustments Following Klystron Replacement ............................................................................. 5-11 5-54. Calibration ............................................................................................................................................ 5-18 5-55. Calibrating Pulse Rate Dial ........................................................................................................... 5-18 5-57. Calibrating Pulse Delay Dial ......................................................................................................... 5-19 5-58. Calibrating Pulse Width Dial ......................................................................................................... 5-19 5-59. Power-Monitor Meter Calibration .................................................................................................. 5-19 5-62. Performance Checks ........................................................................................................................... 5-20 5-64. Frequency Calibration Check ....................................................................................................... 5-20 5-65. Output Power Check ..................................................................................................................... 5-20 REPLACEABLEPARTS .................................................................................................................................... 6-1 6-1. Introduction .......................................................................................................................................... 6-1 6-4. Ordering Information ............................................................................................................................ 6-1 REFERENCES ................................................................................................................................................... A-1 COMPONENTS OF END ITEM LIST Introduction ........................................................................................................................................................ B-1 Integral Components of End Item ...................................................................................................................... B-2 Basic Issue Items ............................................................................................................................................... B-3 ADDITIONAL AUTHORIZATION LIST (Not Applicable) MAINTENANCE ALLOCATION Introduction ........................................................................................................................................................D-1 Maintenance Allocation Chart for Signal Generator AN/USM-47 .......................................................................D-3 Tool and Test Equipment Requirement for Signal Generator AN/USM-47 ........................................................D-4 Remarks..............................................................................................................................................................D-5 EXPENDABLE SUPPLIES AND MATERIALS LIST (Not Applicable) CODE LIST OF MANUFACTURERS ................................................................................................................. F-1 BACKDATING MODEL 626A .............................................................................................................................G-1 MANUALCHANGES ...........................................................................................................................................H-1 ILLUSTRATED PARTS IDENTIFICAION ............................................................................................................ I-1 ii TM 11 -6625-2910-14 Table of Contents Model 626A LIST OF ILLUSTRATIONS Number Title Page Number Title Page 1-1. ( Model 626A SHF Signal Generator....................1-0 5-10. Top View Showing Location of Reflector 1-2. Klystron Tube Warranty .......................................1-2 Tracking Pots. ........................................ 5-13 5-11. Test Setup for Observing Reflector 3-1. Operating Controls and Connectors ....................3-0 Modes..................................................... 5-14 4-1. Timing Sequence in Pulse Section.......................4-1 5-12. Typical Mode Patterns ................................. 5-15 4-2. Block Diagram ......................................................4-2 5-13. Adjustment of Mode Suppressors and 4-3. Block Diagram of Pulse Section ........................... Output Matching Screw .......................... 5-16 Showing Waveforms .....................................4-2 5-14. Calibration Test Setup................................... 5-17 4-4. Input Amplifier and Pulse Rate............................. 5-15. Typical Pulse and Square Wave Multivibrator ..................................................4-3 Oscillograms........................................... 5-18 4-5. Schmitt Trigger and Sync Out Thyratron..............4-3 5-16. Test Setup for Adjusting Output Power......... 5-19 4-6. Delay Multivibrator ...............................................4-4 5-17. Power Supply, V & R Diagram...................... 5-22 4-7. Waveform Comparison .......................................4-4 5-18. Power Supply, Schematic Diagram............... 5-23 4-8. Delay Multivibrator Grid and 5-19. Pulse Section, V & R Diagram ..................... 5-24 Plate Waveforms ...........................................4-4 5-20. Pulse Generator, Schematic Diagram .......... 5-25 4-9. Delayed Sync Out Thyratron and Pulse 5-21. Modulator and RF Generator Sections, Width Multivibrator ........................................4-5 V& R Diagram......................................... 5-26 4-10. Modulator V18 and MOD SELECTOR 5-22. Modulator and RF Generator, Schematic Switch S3 ......................................................4-5 Diagram ................................................. 5-27 4-11. RF Oscillator and Waveguide System .................4-6 4-12. Bunching of Electrons in a Reflex Klystron ..........4-7 ILLUSTRATED PARTS IDENTIFICATION 4-13. Equivalent Circuits of RF Oscillator .....................4-8 1. HP Model 626A, S. H. F. Signal Generator, 4-14. Graph Showing Klystron Oscillation Modes .........4-9 General Arrangement .................................. 2 4-15. Power-Monitor Section ........................................4-9 2. HP Model 626A, S. H. F. Signal Generator, 4-16. Phantom View Showing Output Attenuator ..........4-10 Control Panel, Front View ........................... 4 5-1. Block Diagram of Power Supply...........................5-3 3. HP Model 626A, S. H. F. Signal Generator, 5-2. Rear View of Instrument Showing Control Panel, Rear View ............................ 6 Power Supply and Pulse Sections.................5-4 4. HP Model 626A, S. H. F. Signal Generator, 5-3. View of Klystron Cavity and Frequency Frequency Drive Assembly, ........................ 8 Drive Mechanism ..........................................5-7 5. HP Model 626A, S. H. F. Signal Generator, 5-4. Cutaway Views of Klystron Cavity........................5-9 Cavity Assembly ........................................ 10 5-5. Exploded View of Klystron Cavity and 6. HP Model 626A, S. H. F. Signal Generator, Plunger Drive Mechanism..............................5-10 Directional Coupler Assembly ................... 12 5-6. Detail Showing Reflector Potentiometer 7. HP Model 626A, S. H. F. Signal Generator, Removal ........................................................5-10 Attenuator Assembly ................................ 14 5-7. Right Side View Showing Power Monitor8. HP Model 626A, S. H. F. Signal Generator, ing Bridge Adjustments ..................................5-11 Chassis Front View.................................... 16 5-8. Test Setup for Schmitt Trigger Level 9. HP Model 626A, S. H. F. Signal Generator, Adjustment ....................................................5-12 Chassis, Rear View .................................. 18 5-9. Graph Showing Reflector Tracking 10. HP Model 626A, S. H. F. Signal Generator, Voltage vs Frequency ....................................5-12 Cabinet ...................................................... 20 LIST OF TABLES Number Title Page 1-1. Specifications ......................................................1-0 5-2. 5-3. Power Supply Troubleshooting.............................5-2 RF Generator Troubleshooting.............................5-4 iii Number Title Page 5-4. Pulse Section Troubleshooting ....................... 5-5 5-5. Tube Complement .......................................... 5-6 6-1. Reference Designation Index ......................... 6-2 6-2. Replaceable Parts......................................... 6-9 TM 11-6625-2910-14 SECTION O INTRODUCTION O-1. Scope. This manual describes Signal Generator AN/ USM-47 (Hewlett-Packard Model 626A), and provides instructions for operation and maintenance. The manual includes a components of end item list (COEIL) (app B) and a maintenance allocation chart (MAC) (app D). Repair parts and special tools lists (RPSTL) are included in TM 11-6625-219024P. Calibration procedures are contained in TB 9-6625-77650. The manual applies directly to HF Model 626A signal generators having serial number prefix 1210A- below 01731. For serial numbers prefixed 1202A or lower, see appendix G; for serial numbers 1210A01731 and above, see appendix H. INDEXES OF PUBLICATIONS. a. DA Pain 310-4. Refer to the latest issue of DA Pam 310-4 to determine whether there are new editions, changes, or additional publications pertaining to the equipment. b. DA Pam 310-7. Refer to DA Pam 310-7 to determine whether there are modification work orders (MWO’s) pertaining to the equipment. 38/NAVSUPINST 4610.33BiAFR 75-18, ’ MCO P4610.19B and DLAR 4500.15. O-4. REPORTING EQUIPMENT IMPROVEMENT RECOMMENDATIONS (EIR). EIR’s will be prepared using SF 368 (Quality Deficiency Report). Instructions for preparing EIR’s are provided in TM 38-750, The Army Maintenance Management System. EIR’s should be mailed direct to Commander, US Army Communications and Electronics Materiel Readiness Command, ATTN: DRSEL-ME-MQ, Fort Monmouth, NJ 07703. A reply will be furnished direct to you. O-2. FORMS AND RECORDS. a. Reports of Maintenance and Unsatisfactory Equipment. Maintenance forms, records and reports which are to be used by maintenance personnel at all maintenance levels are listed in and prescribed by TM 38-750. b. Report of Packaging and Handling Deficiencies. Fill out and forward DD Form 6 (Packaging Improvement Report) as prescribed in AR 700-58/NAVSUPINST 4030.29/AFR 71-13/MCO P4030.29A and DLAR 4145.8. c. Discrepancy ix Shipment Report (DISREP) (SF 361). Fill out and forward Discrepancy in Shipment Report (DISREP) (SF 361) as prescribed in AR 55- O-5. ADMINISTRATIVE STORAGE. Administrative storage of equipment issued to and used by Army activities shall be in accordance with TM 740-90-1. O-6. DESTRUCTION OF ARMY ELECTRONICS MATERIEL. Destruction of Army electronics materiel to prevent enemy use shall be in accordance with TM 750-244-2. O-3. O-7. HAND RECEIPTS. Hand receipts for Components of End Item (COEI), Basic Issue Items (BII), and Additional Authorization List (AAL) items are published in a hand receipt manual, TM 11-6625-2910-14HR. This manual is published to aid in property accountability and is available through: Commander, US Army Adjutant General Publications Center, ATTN: AGDL-OD, 1655 Woodson Road, St. Louis, MO 63114. Change 1 O-1 TM 11-6625-2910-14 Model 626A Section I Figure 1-1. HP Model 626A SHF Signal Generator Table 1-1. Specifications Frequency Range: 10 to 15.5 GHz Leakage: Less than minimum calibrated signal generator output Frequency Calibration: Dial read directly in GHz; accuracy better than ±1% Modulation: Internal or external pulsed, FM or square wave Internal Pulse Modulation: Repetition rate variable from 40 to 4000 pps; pulse width variable 0.5 to 10 microseconds Output Range: 10 mW to 1 pW (+10dBm to -9OdBm); attenuator dial directly calibrated in output dbm; swr less than 2. 5 at +10 dBm; 1. 35 at 0 dBm and lower Sync Out Signal: 20to 50 volts amplitude into 1000-ohm load. Better than one microsecond rise time (1) Simultaneous with RF pulse - positive (2) In advance of RF pulse - positive, variable 5 to 300 microseconds Output Monitor Accuracy: Better than +1 dB Output Attenuator Accuracy: Better than ±2% of attenuation in dB introduced by output attenuator External Synchronization: (1) Sine wave, 40 to 4000 Hz, amplitude 5 to 50 volts rms (2) Pulse signals 0 to 4000 pps, 5 to 50 volts amplitude, positive or negative; pulse width 0.5 to 5 microseconds; rise time 0.1 to 1 microsecond Output Connector: 0.850 in. by 0.475 in. waveguide, WR-75 Flat Cover Flange 1-0 TM 11-6625-2910-14 Model 626A Section I SECTION I GENERAL INFORMATION 1-1. b. Measuring sensitivity and selectivity amplifiers, receivers, and other tuned systems. DESCRIPTION. 1-2. The HP Model 626A SHF Signal Generator (Figure 1-1) is a general purpose broadband signal generator which produces RF output voltages from 10 to 15.5 GHz. The output frequency is set with a single control and is directly read on a dial calibrated to an accuracy of 1% or better. The output power level is continuously adjustable from -90 dBm to +10 dBm (1 pW to above 10 milliwatts) over the full frequency range. The attenuator calibration is accurate within +2% of the attenuation in dB introduced by the attenuator. c. Measuring signal-to-noise ratio of RF signals. d. Making slotted line measurements. of e. Investigation of microwave impedances and other transmission line characteristics. f. Measuring frequency response of microwave systems. 1-3. The Model 626A is provided with versatile modulation characteristics. The output can be frequency modulated, square-wave modulated, or pulse modulated by internally or externally generated signals. The Model 626A also provides synchronizing pulses for external equipment being used. 1-4. In addition to producing an accurate and controllable radio-frequency test signal, the Model 626A is useful for the following: a. Testing pulse systems. g. Determining resonant frequency and Q of waveguide cavities. 1-5. The Model 626A has a self-contained modulator and power supply located on a deck at the rear of the instrument. The entire chassis and cabinet are fabricated from aluminum alloy. Guard rails are provided on the front panel to facilitate handling, and to protect the operating controls. Front panel connectors are of the BNC type except for the output connector which is rectangular waveguide. Etched circuit construction is used extensively, and circuit accessibility is very good. Table 1-1. Specifications (Cont’d) TM 11-6625-2910-14 Model 626A Section I 1-6. 1-10. ACCESSORIES FURNISHED. 1-7. The Model 626A is supplied with two different waveguide adapters for connecting the rf output waveguide to either X- or P-band waveguide. The adapters are as follows: Model MX292B used to connect to X-band waveguide; and Model MP292B used to connect to P-band waveguide. INSTRUMENT IDENTIFICATION. 1-11. Refer to paragraph O-1 for coverage on instrument identification and differences. Refer to the ERRATA section of appendix H for changes coverage applicable to all instruments. 1-8. ACCESSORIES AVAILABLE. 1-9. To suppress second and third harmonics an additional40dB, an HP Model M362A Low Pass Filter is recommended. 1-2 TM 11-6625-2910-14 Section II Model 626A SECTION II INSTALLATION 2-11. 2-1. INSPECTION. 2-2. Unpack the instrument upon receipt and inspect it for signs of physical damage such as scratched panel surfaces, broken knobs, etc. If there is any apparent damage, file a claim with the carrier and refer to the warranty page in this manual. 2-12. To operate the Model 626A from a 230-volt +10% source, proceed as follows: 2-3. An electrical inspection should be performed as soon as possible after receipt. See Section V, paragraph 5-62 for performance checks. These procedures make a good test as part of incoming quality control inspection. 2-4. Turn unit off. b. Place 115/230 switch on rear to 230 volt c. Change the line fuse to 2 ampere. AIR FILTER. 2-13. REPACKAGING FOR SHIPMENT. 2-14. The following list is a general guide for repackaging an instrument for shipment. If you have any questions, contact your authorized Hewlett Packard sales representative. a. If possible, use the original container designed for the instrument. b. Wrap the instrument in heavy paper or plastic before placing it in the shipping container. POWER REQUIREMENTS. c. Use plenty of packing material around all sides of the instrument and protect the panel with cardboard strips. 2-7. The Model 626A requires a power source of 115 or 230 volts +10%, 50to60 Hz, which can deliver approximately 200 watts. 2-8. a. position. 2-5. This instrument is equipped with a renewable type air filter. When first placing the instrument into service, the filter must be coated with a dirt-gathering adhesive. We recommend a water-soluble adhesive such as Super Filter Coat from Research Products Corporation. This adhesive comes in a convenient spray can and is available from most heating supply stores or from your authorized Hewlett Packard sales representative (HP Part No. 3150-0002). For preventive maintenance on the air filter, refer to paragraph 5-3. 2-6. 230-VOLT OPERATION. d. Use a heavy cardboard carton or wooden box to house the instrument and use heavy tape or metal bands to seal the container. POWER CABLE. e. Mark the packing box with "Fragile", "Delicate Instrument", etc. 2-9. This instrument is equipped with a three-prong conductor power cable which, when plugged into an appropriate receptacle, grounds the instrument. The offset pin on the power cable three-prong connector is the ground pin. Note If the instrument is to be shipped to Hewlett Packard Company for service or repair, attach to the instrument a tag identifying the owner and indicating the service or repair to be accomplished. In any correspondence be sure to identify the instrument by model number, serial prefix, and serial number. 2-10. To preserve the protection feature when operating the instrument from a two contact outlet, use a three-prong to twoprong adapter and connect the pigtail on the adapter to ground (HP Part No. 12510048). 2-1 TM 11-6625-2910-14 Model 626A Section III 1. Turns on line power to the instrument. 2. Frequency control (not labeled) is used to set to desired RF output frequency. Frequency dial is read directly in KILOMEGACYCLES (GHz). 3. ZERO SET control is used to zero- set the power-monitor meter. 4. PWR SET control is used to establish the correct power level fed to the output attenuators. 5. OUTPUT ATTEN control adjusts the RF output level from + 10 dBm to - 90 dBm (10 mW to 1 pW). 6. FM AMPLITUDE control adjusts the frequency deviation of the output signal when internal or external frequency modulation is employed. 7. FM PHASE control adjusts the phase of frequency modulation from approximately +90 degrees to - 90 degrees with respect to the SWEEP OUT signal only when internal frequency modulation is employed. 8. MOD SELECTOR switch is used to select the desired type of modulation to be applied to the RF output signal. 9. PULSE RATE control adjusts the repetition rate of the RF output pulse or square wave when the MOD SELECTOR is set to INT or SQ WAVE. The X1or X10 positions of the SYNC SELECTOR determines the multiplying factor to be applied to the reading of the calibrated PULSE RATE dial. 10. PULSE DELAY control adjusts the time delay between the leading edge of the SYNC OUT pulse and the RF output pulse from 3 to 300 microseconds when the MOD SELECTOR is set to INT. 11. PULSE WIDTH control adjusts the width of the RF output pulse from 0.5 to 10 microseconds when the MOD SELECTOR is set to INT. 12. SYNC SELECTOR switch is used to select the type of synchronization to be employed by the signal generator during internal pulse modulation of the RF output signal. 13. RF OUTPUT: M band type WR-75 waveguide, cover type flange. 14. DELAYED SYNC OUT connector is the output for delayed sync pulses in either square-wave or pulse operation. These pulses are controlled by PULSE DELAY. 15. SYNC OUT connector is the output for sync pulses in either square- wave or pulse operation. 16. SYNC IN connector is the input for sync pulses. These pulses are used only when MOD SELECTOR is set to INT and SYNC SELECTOR to EXT-, EXT + or a. 17. EXT MOD/SWEEP OUT: This connector is used as an input for external modulation signals when MOD SELECTOR is set to EXT FM, EXT- or EXT +. The connector is also used as an output for a sweep signal which occurs only when MOD SELECTOR is set to INT FM. Figure 3-1. Operating Controls and Connectors 3-0 TM 11-6625-2910-14 Section III Model 626A SECTION III OPERATING INSTRUCTIONS SET to obtain a meter indication exactly on the POWER SET index (red line at center of scale). d. Set OUTPUT ATTEN for the desired RF output level in dBm as indicated on the calibrated attenuator scale. 3-1. INTRODUCTION. 3-2. This section contains instructions for the various modes of operation; each is covered in the operating procedure, paragraph 3-6. Front panel controls and connectors and their uses are shown in Figure 3-1. 3-10. 3-3. SQUARE-WAVE OUTPUT. a. After obtaining the desired CW level as described in paragraph 3-9, set MOD SELECTOR to SQ WAVE. b. Set SYNC SELECTOR to the X1 or X10 position, and adjust PULSE RATE to obtain the desired squarewave frequency. c. A synchronizing pulse coincident with the rise of each cycle of square wave is available at the SYNC OUT connector on the front panel. HARMONICS. 3-4. At output levels between 50 and +10 dBm, harmonics in the RF output are at least 20 dB below the fundamental frequency. Normally harmonics will not degrade measurements such as determining sensitivity of tuned receivers or tuned systems. However, when measuring standing wave ratios, accuracy can be increased by using a low-pass filter which suppresses second and third harmonics. A low-pass filter with a broad stop band, such as the HP Model M362A is recommended. 3-5. The signal generator attenuator will affect only the fundamental frequency, and therefore harmonics can be identified. 3-6. 3-11. INTERNAL PULSE MODULATION. a. After obtaining the desired CW level as described in paragraph 3-9, set MOD SELECTOR to INT. b. Set SYNC SELECTOR to X1 or X10, and adjust PULSE RATE to obtain the desired pulse repetition rate. OPERATING PROCEDURE. 3-7. The operation of the Model 626A consists of adjusting the two major sections: the RF section, and the modulator section. Adjust the RF section first, since this adjustment establishes the output power reference level, for the output attenuators. 3-8. After turning the instrument on, allow it at least 5 minutes to reach a stable operating temperature. If the ambient temperature is below 100C(50uF) a longer warmup period is necessary. c. Adjust PULSE WIDTH to obtain the desired width of RF output pulse. Note The klystron tube used in this instrument is expensive and has a shorter life than that of the conventional vacuum tube. When the MOD SELECTOR switch is set to OFF, filament and plate voltages are still present on the klystron tube, and therefore power should be removed from the instrument when it is not in use in order to increase the useful life of the tube. Average tube life approximates 1000 hours and the warranty period approximates 500 hours. 3-12. 3-9. d. Adjust PULSE DELAY to obtain the desired delay between the leading edge of the RF output pulse and synchronizing pulse obtained at SYNC OUT. e. To synchronize any external equipment, use the SYNC OUT and/or DELAYED SYNC OUT pulses. EXTERNAL PULSE MODULATION. a. After obtaining the desired CW level as described in paragraph 3-9, set MOD SELECTOR to EXT + or EXT to match the polarity of the external modulating pulse. b. Connect the modulating pulse to EXT MOD connector. The modulating pulse must have an amplitude of at least 15 volts peak. 3-13. INTERNAL FM AT LINE FREQUENCY. a. After obtaining the desired CW level as described in paragraph 3-9, set MOD SELECTOR to INT FM and SYNC SELECTOR to a . b. Set FM AMPLITUDE control to the full counterclockwise position, then advance it slowly to establish the desired degree of RF frequency deviation about the center frequency. If the control is advanced too far, the modulating voltage may drive the klystron out of the desired mode of oscillation. CW OUTPUT. a. Set frequency dial for desired frequency output. b. Set MOD SELECTOR to OFF, and adjust ZERO SET to obtain a power-monitor meter indication exactly on the ZERO SET index. c. Set MOD SELECTOR to CW, and adjust PWR 3-1 TM 11-6625-2910-14 Model 626A Section III c. Set FM AMPLITUDE control to the full counterclockwise position, then advance it slowly to establish the desired degree of FM about the center frequency. If the control is advanced too far, the modulating voltage may drive the klystron out of the desired mode of oscillation. The FM PHASE control cannot be used to control the phase of modulating signals supplied from an external source. 3-14. To observe a presentation of the mode pattern, connect the RF output through a detector to the vertical plates of an oscilloscope and the SWEEP OUT signal to the horizontal plates of the oscilloscope. This method of viewing the mode pattern is recommended when adjusting the reflector- tracking potentiometers. 3-15. EXTERNAL FM. 3-16. To observe a presentation of the mode pattern, connect the RF output through a detector to the vertical plates of an oscilloscope and connect the external frequency modulation signal to the horizontal plates of the oscilloscope. a. After obtaining the desired CW level as described in paragraph 3-9, set MOD SELECTOR to EXT FM. b. Connect the external frequency modulation signal to the EXT MOD connector. The modulating signal must have an amplitude of 20 to 30 volts rms. 3-2 TM 11-6625-2910-14 Section IV Model 626A SECTION IV PRINCIPLES OF OPERATION 4-1. INTRODUCTION. 4-2. The Model 626A contains five main circuit sections and a regulated power supply. The five main circuit sections, and all front panel controls and connectors are shown in block diagram, Figure 4-2. These circuits provide FM, CW, squarewave, and pulse modulated signals in the 10- to 15.5GHz range. 4-3. sine waves and positive pulses, and with S2 at position 3 (EXT-), V9 is an input inverter amplifier for negative pulses. (1) In position 1 or 2, the input signal is applied to the grid of V9A and the grid of V9Bis grounded through capacitor C22. The output signal, in phase with the input signal, is taken from the plate of V9B and couples to V10 which is arranged as a Schmitt Trigger. PULSE SECTION. (2) 4-4. This section generates all pulses for internal modulation and synchronizing external equipment. The circuits of the pulse section are shown in Figure 4-3, and explained in the following paragraphs. The time relationship between pulses is shown in Figure 4-1 4-5. INPUT AMPLIFIER MULTIVIBRATOR. AND PULSE RATE 4-6. The functions of input amplifier and pulse rat multivibrator V9 are dependent upon the position of the SYNC SELECTOR switch. Refer to Figure 4-4. b. With S2 in positions 4 (X1l) and 5 (X10), V9 becomes a free running multivibrator. The frequency of oscillation is determined by time constants of the RC networks and a variable positive voltage towards which the grids are returned. (1) a. 1(a) or With SYNC SELECTOR switch S2 at position 2 (EXT +), V9 is an input amplifier for In position 3, the input signal is applied to the grid of V9B and the grid of V9A is grounded through capacitor C22. The output signal, 1800 out of phase with the input signal, is taken from the plate of V9B and coupled to V10. In position 4 (X1) frequency of oscillation is from 40to 400 pps and the RC network consists of C16-R35 and C20-R42. Figure 4-1. Timing Sequence in Pulse Section 4-1 TM 11-6625-2910-14 Model 626A Section IV Figure 4-2. Block Diagram Figure 4-3. Block Diagram of Pulse Section Showing Waveforms 4-2 TM 11-6625-2910-14 Section IV Model 626A 4-13. The voltage divider composed of R43, R44, R45, and R46 establishes the no-signal level on the V1OA grid below the lower trigger level or at approximately -234 volts. 414. Maximum sensitivity of the schmitt trigger is obtained when the average DC level of the input signal is so set that the signal is symmetrical with respect to the two trigger levels. The average DC level at the input to V10 is raised or lowered by adjustment of Trigger Level Adj. (R44), which in turn adjusts the duty cycle of the square-wave output. 415. The signal which will be used for square-wave modulation is provided by the schmitt trigger. To avoid loading the output of V1OB, the squarewave modulating voltage is taken from the plate of V1OA, and is coupled to modulator V18 when MOD SELECTOR switch S3 is in SQ WAVE. Figure 4-4. Input Amplifier and Pulse Rate Multivibrator 4-16. The output signal is taken from the plate of V10B for triggering thyratron V11. (2) In position 5 (X10) frequency of oscillation is from 400 to 4000 pps and the RC network consists of C15R35 and C21-R42. Note that C15 and C21 are one tenth the capacity of C16 and C20, and thus the RC time in the X10 position is one tenth of that in the X1 position, giving a frequency multiplication of ten. 4-7. PULSE RATE control, R34, varies the voltage towards which the timing capacitors tend to discharge, hence the time it takes the instantaneous grid voltage to reach cut off value in the discharge period of the RC networks. 4-8. The two sections of V8 act as clamping diodes which prevent V9 grids from drawing grid current on their positive swing. Both diodes are clamped to-300 volts and they conduct whenever the instantaneous grid voltages go positive with respect to -300V. This action prevents any transients from appearing in the plate circuits, thereby improving the output waveform. Figure 4-5. Schmitt Trigger and Sync Out Thyratron 4-17. 4-9. The output signal taken from the plate of V9B is coupled, by capacitor C23, to the grid of V1OA. 4-10. SYNC OUT THYRATRON. 4-18. The output of V1OB is differentiated by C25 and R54. The sharp positive spike fires sync out thyratron V11 (Figure 4-5) by driving its grid positive. A large negative pulse (-130 volts peak) is developed in the plate circuit of V11 and is fed through C38 and R55 to delay multivibrator V13. A positive pulse (30 volts peak) appears at the cathode of V I and is fed to the SYNC OUT connector through C26. This sync signal is simultaneous in time with the front of the original pulse established by the pulse rate multivibrator or by an external source of sync signals. The time relationships are indicated in Figure 4-1. SCHMITT TRIGGER. 4-11. A pulse of fast rise and decay time is required for triggering thyratron V11. Therefore the output from V9 is passed through a schmitt trigger circuit before being applied to sync out thyratron V11. The schmitt trigger circuit is shown in Figure 4-5. 4-12. Transition from one state to the other in a schmitt trigger circuit(a direct coupled multivibrator) is very fast, which results in a square wave output of sharp waveform. V10 reverses conduction when the rise of the input signal reaches an upper trigger level, and again when the decay of the input signal goes through a lower trigger level. These trigger levels are established by the change in potential in the common cathode circuit which results from the difference in conduction through two sections of V10. The upper trigger level is established when V1OB is conducting and is approximately 223 volts. The hysteresis of the circuit is 10-11 volts which places the decaying trigger level at approximately 233 volts when V1OA is conducting. 4-19. DELAY MULTIVIBRATOR. 4-20. Delay multivibrator V13 (Figure 4-6) produces an output pulse whose width is variable from 3 to 300 us with respect to its leading edge t1, see Figure 4-1. Its trailing edge establishes time reference t2. The width of the output pulse is controlled by setting PULSE DELAY control, R80. 4-3 TM 11-6625-2910-14 Model 626A Section IV 4-23. Rapid return of V13B grid to the no signal level is required so that the delay multivibrator will be prepared to receive the next pulse incoming from VII. Since at high pulse repetition rates the period between pulses is short (250 µs at 4000 pps), interaction would occur if grid recovery time is short. 4-24. The relation between changes in grid level and pulse width is indicated in the waveform diagram Figure 4-8. The width of the output pulse is dependent upon two things: the RC time constant of C41-R65 and the level of potential on the V13B grid when the delay multivibrator is in the no-signal condition. While the RC time can not be varied, the level of potential on the V13Bgrid can be raised or lowered by changing PULSE DELAY control. For example, when PULSE DELAY is set so that the no-signal level on V13B grid is approximately -390 volts, the positive pulse from V13A will drive V13B grid very little above cutoff, conduction time of V13B will be brief, and therefore the width of the output pulse will be greatly shortened. Figure 4-6. Delay Multivrator 4-21. Delay multivibrator V13, is arranged as a one shot multivibrator, with a diode clamp in each of its grid circuits. Diode V12A clamps V13A grid to prevent it from going more positive than 300 volts. Diode V12B clamps V13B grid to prevent it from going more negative than a level determined by the setting of the PULSE DELAY control, a level which is somewhere below cutoff. Under no signal conditions V13A is conducting, V13B is cut off, andVl2B is conducting. When the circuit is in the no-signal condition, the potential onV13Bgrid is established through V12Band is essentially the same as the potential on V12B plate. 4-22. When the large negative pulse from V11 is applied to the grid of V13A, conduction in V13Aceases, and the positive signal developed in the plate of V13A is coupled to the grid of V13Bthrough timing capacitor C41. V13B conducts, V12B cuts off, and C41 discharges through R65 towards 650 volts, pulling the grid of V13B more negative until cutoff is reached. V13A then starts to conduct, and the negative signal developed in the plate of V13A is coupled to the grid of V13B, driving the V13B grid negative from cutoff by an amount equal to the plate swing of V13A. Diode V12Bstarts to conduct, C41 discharges through V12B, and the V13B grid is returned to the no-signal condition in a very short time. Waveforms shown in Figure 4-7 illustrate the decrease in recovery time obtained by use of grid clamp V12B. Figure 4-8. Delay Multivibrator Grid and Plate Waveforms 425. With PULSE DELAY at minimum, variable resistor R78 adjusts the minimum interval between the leading (t1) and trailing(t2) edges of the output pulse, thus effecting minimum delay of the RF output pulse with respect to t1. 4-26. The output of Vl3Bis differentiated by C27 and R66, and the negative spike, corresponding to t1 is eliminated through diode CR1. The positive spike, representing time reference t2, is passed to delayed sync out thyratron V14. 4-27. DELAYED SYNC OUT THYRATRON. 4-28. The action of delayed sync out thyratron V14 (Figure 4-9) is similar to that described for sync out thyratron V11 (paragraph 4-17). The positive differentiated spike from V13 fires the thyratron. The positive pulse (30-volt peak) developed in the V14 cathode circuit is fed to the DELAYED SYNC OUT connector, and the large negative pulse developed in the V14 plate circuit is coupled to width multivibrator V15. 4-29. Figure 4-7. Waveform Comparison PULSE WIDTH MULTIVIBRATOR. 4-30. The action of pulse width multivibrator V15 (Figure 4-9) is similar to that of delay multivibrator 4-4 TM 11-6625-2910-14 Section IV Model 626A paragraph 4-24. The pulse width multivibrator provides an output pulse whose width is variable from 0.5 to 10 µs. The trailing edge of the V15B output pulse establishes time reference t3, see figure 4-1. With pulse width at minimum, variable resistor R85 adjusts the minimum interval between the leading (t2) and trailing (t3) edges of the output pulse, thus effecting minimum width of the RF output pulse with respect to t2 . 4-32. The V15B output pulse is coupled to the grid of V18B in the modulator section when the MOD SELECTOR switch is set to INT. 4-33. Figure 4-9. Delayed Sync Out Thyratron and Width Multivibrator MODULATOR SECTION. 4-34. The modulator section (Figure 4-10) includes modulator tube V18 and MOD SELECTOR switch S3. This section receives all pulse and squarewave modulation signals to be applied to the RF oscillator section. The modulator tube functions only in positions 4, 5, 6, and 7 of S3. In positions land2 FM signals are applied to the klystron reflector. In position 3 no modulation signal is applied to the klystron, thus the RF output signal is a continuous wave. Circuit conditions at each position of S3 are as follows: V13 (paragraph 4-19) except that there is no diode in the V15B grid circuit to shorten recovery time. Normal recovery time is adequate to return the circuit to the no signal condition before the next pulse is received from V14. 4-31. BiasfortheV15B grid is applied through a voltage divider, R82R85, which includes variable resistor R83, brought out to the front panel as the PULSE WIDTH control. The relation between level of grid potential and width of output pulse was discussed in a. Position 1 (EXT FM) -An externally-supplied FM signal, applied at the EXT MOD/’SWEEP OUT connector, is placed across variable resistor R115 (FM Figure 4-10. Modulator V18and MOD SELECTOR Switch S3 4-5 TM 11-6625-2910-14 Model 626A Section IV Figure 4-11. RF Oscillator and Waveguide System oscillates. Oscillation continues for the duration of the pulse, and then the V18 circuit returns to the no-signal condition, again driving the klystron reflector outside the operating mode. AMPLITUDE control), and then coupled by capacitor C35 to the klystron reflector. b. Position 2 (INT FM) -An internally-supplied FM signal of the same frequency as the line voltage is placed across R115 (FM AMPLITUDE control), and then coupled to the klystron reflector. This signal, taken from secondary winding B of power supply transformer T2 by leads P7 (8) and P7 (7), is applied to the modulator section through a phasedetermining network which includes the FM PHASE control. The FM signal voltage is also supplied to the EXT MOD/ SWEEP OUT connector. f. Position 6 (SQ WAVE) -The square-wave signal, from the VIOA section of the schmitt trigger is placed on the V18B grid. As described for position 5, the resulting action alternately changes the klystron reflector voltage so that the klystron moves in and out of oscillation. g. Position 7 (EXT-) -The action in this position is identical to that described for position 5 except that the negative pulses that are applied to the modulator section are supplied from an external source at the EXT MOD/SWEEP OUT connector. h. Position 8 (EXT+) -The action in this position is similar to that described for position 7 except that externally supplied pulses are applied to V18A grid. V18A conducts, V18B cuts off and allows the klystron to oscillate. In the EXT+ position V18 acts as a pulse inverter. c. Position 3 (CW)-In this position modulation is not applied to the klystron reflector and the RF output signal generated by the RF oscillator is a continuous wave. d. Position 4 (OFF) – In this position the klystron reflector is tied to the plate of V18B. With the modulator section in the no-signal condition, V18A is cut off and V18B is conducting. The drop across the V18B plate load resistor(approximately 60 volts) drives the reflector outside the operating mode, and there is no oscillation. 4-35. The action of diode V16 protects the klystron from drawing reflector current. V16 is connected across the cathode and the reflector, and conducts in the event the klystron reflector goes positive with respect to the klystron cathode. e. Position 5 (INT) -In this position, modulating voltage is supplied from width multivibrator V15. In the no signal condition the circuit is as described for position 4. When a negative pulse from V15 is placed on its grid, V18B cuts off. Potential on the V18B plate rises, returning the klystron reflector to the operating level, and the klystron 4-36. RF OSCILLATOR SECTION. 4-37. The RF oscillator section (Figure 4-11) of the Model 626A is essentially an all waveguide system, 4-6 TM 11-6625-2910-14 Section IV Model 626A employing a reflex klystron tube mounted in a plunger tuned cavity for generation of the RF energy. The energy from the cavity is coupled to a power set attenuator (uncalibrated) which adjusts the power level applied to the calibrated attenuator. The level at the input of the calibrated attenuator is monitored by a compensated thermistor bridge which operates a front panel meter. Monitoring is accomplished by sampling the RF energy through a waveguide directional coupler which feeds the sampled RF energy to a thermistor located in one leg of the bridge. The calibrated attenuator is a rotary type, operating in circular waveguide with a transition to rectangular waveguide at its output. 4-38. REFLEX KLYSTRON OPERATION. 4-39. The resonant circuit of the RF oscillator includes klystron resonator-grid capacitance, beam admittance, and the primarily inductive impedance of the external cavity. The cavity is fitted with a movable plunger which changes cavity dimensions, thereby varying the impedance of the oscillator resonant circuit. With a change in impedance, the frequency of oscillation is changed. Figure 4-12. Bunching of Electrons in a Reflex Klystron 4-40. Fig 4-13a and Fig 4-13b show equivalent circuits of a reflex klystron oscillator. In the following discussion of how oscillations are sustained in a reflex klystron oscillator, the presence of a low amplitude RF voltage across the resonator grids is assumed. As in any oscillator, this initial voltage is supplied by the thermal agitation noise. 4-44. The time that the electrons spend in the drift space is adjusted by changing the reflector voltage. As reflector voltage is increased in the negative direction, electrons a, b, and c spend less time in the drift space. As reflector voltage is 1, 1 1 decreased electrons a b , and c (Figure 4-12) travel farther into the drift space and take a longer time (tn1) to return to the grids. At the low end of the frequency band (10. 0 to 12. 8 GHz.), the reflector voltage is adjusted so that the number of oscillations (N) that occur at the grid while the electrons are in the drift space is equal to 3-3/4 cycles. At the high end of the frequency band (12. 8 to 15. 5 GHz.), the reflector voltage is adjusted so that the number of oscillations equals 4-3/4 cycles. When the oscillator is operating with 3-3/4 cycles drift time it is known as operating in the 33/4 reflector mode. A plot of reflector modes with respect to frequency and reflector voltage is given in Figure 4-14. 4-41. Electrons emitted from the cathode toward the resonator grids are velocity modulated, i.e., the electrons are accelerated or decelerated according to the phase of the RF voltage existing across the resonator grids. After leaving the resonator grids, the electrons encounter a retarding electric field set up by the negative reflector voltage and are repelled back toward the grids. Since the electrons have been velocity modulated they tend to form in bunches when they arrive at the grids. 4-42. This bunching of electrons is illustrated in Figure 4-12, which shows the transit time relationship of electrons while in the drift space between the resonator grids and the reflector. Consider an electron (a) leaving the grids at time t1. The voltage of the RF signal on the grids is such that the electron receives energy and is accelerated into the drift space. It arrives back at the grids at time tn. An electron (b) leaving at time t2 receives no acceleration because the RF signal is now at zero volts. Thus electron (b) does not travel as far into the drift space and arrives back at the grids at the same time as electron (a). Electron (c) leaving at time t3 is decelerated since the RF signal has reversed voltage polarity since time t1. Electron (c) travels a shorter distance into the drift space and arrives back at the grids at the same time as electrons (a) and (b). 4-43. When bunched electrons arrive back at the grids at a time when the RF signal tends to retard their return, they deliver energy to the grids and sustain oscillations in the resonant cavity. 4-7 4-45. RF OSCILLATOR TUBE. 4-46. The RF oscillator tube is a Varian type V39B reflex klystron operating in a tunable cavity resonator. The klystron and cavity assembly are shown in Fig 5-4a and Fig 5-4b. The klystron is constructed with two irises located opposite each other and near the resonator grids. One iris looks into the external cavity and the other into the output system. 4-47. The klystron cavity system in the Model 626A operates on the 3/4 wavelength cavity mode, and oscillation of both the 33/4 and 4-3/4 reflector modes are employed to cover the frequency band from 10.0 to 15.5 GHz. The 3-3/4 mode is used from 10.0 GHz to approximately 12. 8 GHz. At this frequency the tuning mechanism actuates mode switch S4 to decrease the voltage applied to the reflector by approximately 250 volts. This action places the system on the 4-3/4 mode for the remainder of the band from approximately 12.8 to 15.5 GHz. TM 11-6625-2910-14 Model 626A Section IV Figure 4-13. Equivalent Circuits of RF Oscillator 4-8 TM 11-6625-2910-14 Section IV Model 626A Figure 4-14. Graph Showing Klystron Oscillation Modes 4-49. Voltage is applied to the klystron reflector from variable resistor R96. The movable arm of R96 is ganged to the frequency drive in such manner that voltage on the reflector is automatically tracked with frequency in the desired reflector mode. 4-48. As shown in the plot of modes, Figure 4-14, the 5/4 wavelength cavity mode interferes with the 3-3, reflector mode at the lower end of the band. This mode is suppressed by means of two tapered loads adjoining the cavity, parallel to the plunger, and by an adjustable load in the klystron cavity. The mode suppressors al shown in Figure 5-13. Since klystrons possess a natural tendency to oscillate on the 1/4 wavelength cavity mode, and since this mode is undesirable, it suppressed by the use of a small cylindrical load coupled to the cavity; a small screw matches the cavity to this load. The matching screw is effective shorted out of the circuit at approximately 11 GHz al below by a shorting switch actuated by a cam on the frequency-drive shaft (Figure 5-13). 4-50. POWER-MONITOR SECTION. 4-51. The power-monitor section monitors the RF power level at the input to the calibrated attenuator (OUTPUT ATTEN DBM). The power-monitor section includes an uncalibrated attenuator (PWR SET) which adjusts the level of power applied to the calibrated attenuator, and a thermistor bridge which monitors the power applied to the calibrated attenuator. Refer to Figure 4-15. Figure 4-15. Power-Monitor Section 4-9 TM 11-6625-2910-14 Model 626A Section IV 4-52. RF power from the klystron is coupled to the uncalibrated attenuator which is brought out to the front panel as the PWR SET control. Power from the uncalibrated attenuator is coupled directly to the calibrated attenuator. Power delivered to the calibrated attenuator is sampled by a specially designed directional coupler and applied to one leg of the temperature compensated thermistor bridge(RT123). Power monitor meter M1 is connected across the bridge and when the bridge is balanced the meter reads ZERO SET. To bring the bridge into balance adjust the ZERO SET control. If the bridge is balanced before the power is sampled and when the sampled power causes the meter to read 0 dBm, the power level at the input to the calibrated attenuator is + 10 dBm (10 mW). 4-53. Thermistor RT106 connected in series with the meter acts as a sensitivity regulating device, necessary because of the characteristic of thermistor bridges to increase in sensitivity as the ambient temperature increases. Thermistor RT102 in the network shunted across the bridge is a temperature-compensating device. Since RT123 is temperature sensitive, the bridge could drift appreciably from its zero setting with changes in ambient temperature. RT102 compensates for this tendency. With changes in the voltage across the bridge, current through thermistor RT102 also changes, and its resistance varies in such manner as to regulate the current through RT123. The regulation of current through RT123 tends to keep the bridge in balance by counteracting any change in current through RT123 due to ambient temperature changes. Thus the bridge can be zeroset and will remain in balance to a relatively high degree. 4-54. Figure 4-16. Phantom View Showing Output Attenuator fixed end sections. The end sections are rectangular to round waveguide transitions in which the resistive films are normal to the E field of the applied wave. The construction is symmetrical. 4-57. When all films are aligned, the E field of the applied wave is normal to all films and no attenuation occurs. When the center section is rotated through an angle θ, the E field may be considered as resolved into two components: E sin θ in the plane of the film and E cos θ normal to the plane. The E sin θ component will be absorbed by the film while the E cos θ component, now oriented at an angle θ with respect to the applied wave, will be passed unattenuated to the third section. When it encounters the third film, the E cos θ component will be split into two components: the E cos θ sin θ component 2 which will be absorbed by the film, and the E cos θ component which will emerge with orientation identical to the original wave. OUTPUT ATTENUATOR SECTION. 4-55. The output attenuator section consists essentially of two broadband, precision waveguide attenuators operating in series and ganged to the OUTPUT ATTEN DBM control. The OUTPUT ATTEN is calibrated to read the output in dBm. 4-56. Each attenuator consists of three sections of waveguide in tandem. In each section a resistive film is placed across the guide as shown in Figure 4-16. The middle section is a short length of round guide which is free to rotate axially with respect to the two 4-58. The attenuation is thus a function only of the angle to which the center section is rotated and is almost completely independent of frequency. In terms of dB the attenuation is equal to 40 log cos 0. Attenuation through both attenuator sections in series is twice the attenuation through one of them, i.e. [2 (40 log cos 9)1, and attenuation up to 100 dB maybe introduced. 4-10 TM 11-6625-2910-14 Section V Model 626A SECTION V MAINTENANCE 5-1. 5-13. For simplification, only tubes are referenced in the troubleshooting charts, but it should be remembered that components associated with referenced tubes are also failure possibilities. When testing the signal generator it is recommended that line voltage be applied through a variable transformer, and that the transformer be adjusted to deliver a voltage at the low end of the rated 103to 127-volt range. An instrument in good condition should operate satisfactorily from any line voltage within the rated range, but where there is marginal operation(from weak tubes, etc), weaknesses become easier to trace at low line voltages. INTRODUCTION. 5-2. This section provides maintenance and service information for the Model 626A SHF Signal Generator. The section includes recommended test equipment, replacement procedures for tubes, repair and adjustment procedures, and troubleshooting charts. Also included are performance checks which verify proper instrument operation. 5-3. CLEANING THE AIR FILTER. 5-4. The air filter for the Model 626A is located behind the louver on the front panel. Inspect the air filter regularly, and clean it before it becomes dirty enough to restrict air flow. To remove and clean the air filter, proceed as follows: 5-14. 5-15. Correct operation of the power supply is vital to proper operation of the signal generator. Noise or variation in the regulated voltages causes other circuits to operate in a random or erratic manner. It is advisable to make a voltage check of the power supply whenever the instrument is suspected of marginal operation. This eliminates factors such as low voltages or poor regulation which cause unsatisfactory performance in other sections of the instrument. a. Remove filter from instrument front panel by removing the four machine screws at the corners. b. Wash filter in warm water and detergent. c. Dry filter thoroughly and coat it with filter adhesive. We recommend Super Filter Coat from Research Products Corporation. This adhesive comes in a convenient spray can and is available from most heating supply stores or from your authorized Hewlett Packard sales representative HP Part No 3150-0002). 5-5. POWER SUPPLY. 5-16. The power supply section consists of three interdependent electronically-regulated voltage supplies, furnishing -300, -700, and -1250 volts as measured from chassis ground and an unregulated supply furnishing - 210 volts. TEST EQUIPMENT. a. The -300 volt regulated supply furnishes voltage for operation of the pulse generator. It also furnishes a regulated 150 volts for the power monitor bridge. This voltage is taken from an additional voltage regulator tube (V3), included between chassis ground and the -300 volt supply. 5-6. Test equipment required for use in maintaining and checking performance of the Model 626A is listed in Table 5-1. Equipment having similar characteristics can be substituted for the equipment listed. 5-7. TROUBLESHOOTING. 5-8. LOCATING TROUBLE. b. The -400 volt regulated supply, stacked with the -300 volt supply, furnishes -700 volts (beam supply) to the klystron cathode and pulse circuits. c. The -550 volt regulated supply, stacked with the -300 and -400 volt supplies, furnishes -1250 volts(reflector supply) to the klystron reflector. 5-9. Always start locating trouble with a thorough visual inspection for burned-out or loose components, loose connections, or any condition which suggests a source of trouble. Check tubes for open filaments by touching tubes and replace all that are cold. Replacing a cold tube, in most cases, will restore the generator to normal operation. Check the fuse to see that it’s not open. 5-17. The separate supplies and their relationships are shown in a block diagram, Figure 5-1. The regulated supplies are stacked, and voltage regulator tube V7 in the 550 volt supply furnishes the reference voltage for the whole supply. 5-10. If trouble cannot be isolated to a bad component by a visual inspection or a cold tube, the trouble should then be isolated to a circuit section. Isolation to a circuit section can best be accomplished by using block diagram, Figure 4-2. 5-18. After the instrument is turned on, there is a 30second delay before the -300 and -400 volt supplies are energized, which permits tube filaments to heat before klystron beam voltage and tube potentials are applied. Thermal relay K1 in the power supply input holds the transformer T1 primary 5-11. TROUBLESHOOTING CHARTS. circuit open for 30 seconds after power is applied. 5-12. Troubleshooting charts, Table 5-2, Table 5-3, and Table 5-4, list checks and symptoms, possible causes, and remedies of various troubles. The power supply should be checked first; refer to paragraph 5-14. 5-1 TM 11-6625-2910-14 Section IV Model 626A Table 5-1. Required Test Equipment Table 5-2. Power Supply Troubleshooting 5-2 TM 11-6625-2910-14 Section V Model 626A Figure 5-1. Block Diagram of Power Supply 5-19. It will be noticed in the schematic diagram a the power supply, Figure 5-20, that V6, the control tube for the 700 volt supply, has a divided plate loan consisting of R21 and R25-R26. R21 acts as the plat load before the thermal relay is actuated while R25 R26 act as the plate load after the relay trips. 5-22. REPAIR. 5- 23. CABINET REMOVAL. 5-24. To remove Model 626A from its cabinet proceed as follows: 5-20. When measuring voltages in power supply, the procedure given in Table 52 should be followed. This permits the voltmeter common to be attached to -70( volt bus at all times, while the dc probe is moved from point to point. Use of polarity switch on the voltmeter will be required only when measuring +700 and +40C volts to chassis ground. a. Position instrument so that it is resting on front panel guard rail handles. b. Remove four screws on the back of the cabinet, and lift the cabinet from instrument chassis. 5-25. TUBE REPLACEMENT CHART. 5-26. Tubes used in Model 626Aare listed in Table 5-5. Any tube may be replaced with a tube having corresponding RETMA standard characteristics. When tube replacement requires that an adjustment be performed, Table 5-5 references paragraph or table where pertinent adjustment information is given. It is recommended that tubes be checked by substituting new tubes of the same type; if no improvement in performance is noted, return original tube to the socket. WARNING When measuring voltages from points on the regulator card which have dc potential to ground, use a plastic encased multimeter. When using metal case vtvm’s exercise great care since metal cabinets will beat high negative potentials. 5-21. Adjust line voltage from 103 to 127 volts while measuring output voltages from the regulated supply The regulated voltages may vary +1% with this line voltage change. 5-27. SERVICING ETCHED CIRCUIT BOARDS. 5-28. To service etched circuit boards the following steps are recommended. 5-3 TM 11-6625-2910-14 Model 626A Section V Figure 5-2. Rear View of Instrument Showing Power Supply and Pulse Sections Table 5-3. RF Generator Troubleshooting Symptom Possible Cause Remedy With MOD SELECTOR set to OFF Power- monitor meter No supply voltage not indicating Measure bridge supply voltage across end tap (orange lead) R98 (Figure 5-7) and ground; should be approximately 2 to 3 volts. Check -150 volt supply. Defective VR tube V3 Replace V3; readjust ZERO SET (para 5-41) Open meter Disconnect meter; check continuity. Caution: 200 µA movement Power- monitor meter pins upscale or downscale Shorted or open component on one side of bridge causing unbalance Disconnect one side of meter. Measure bridge supply voltage at R98 (see remedy step above) for 2 to 30 volts. Measure voltage between each side of bridge and ground to determine side at fault. The voltage at both midpoints on each side of the bridge should be 1/2 voltage applied to bridge from R98. Power- monitor meter pins to left below zero Open thermistor RT123 Replace thermistor mount. Recalibrate power- monitor meter (para 5-59) 5-4 TM 11-6625-2910-14 Model 626A Section V Table 5-3. RF Generator Troubleshooting (cont’d) Symptom Possible Cause With MOD SELECTOR set to OFF (cont’d) Power- monitor meter pins High bridge voltage; defective to right upscale VR tube V3 With MOD SELECTOR set to CW Power- monitor meter indicates weak output a. Replace V3 Shorted thermistor mountingpost insulator. (One post is insulated from mounting by mica washer which also acts as bypass capacitance.) It is recommended that entire mount be replaced because of difficulties in adjusting mount frequency response after reinsulating post (para 5-59) Incorrect tracking adjustments Check reflector tracking adjustments (para 5-50). Observe mode patterns. Defective klystron Replace klystron, cavity, and frequency drive mechanism (para 5-29) Extraneous material in cavity (braid, filings, polyiron chips, etc) Remove foreign matter Do not apply excessive heat. b. Remove a damaged component by clipping leads near component. e. side. Solder replacement components from the conductor 5-29. KLYSTRON TUBE REPLACEMENT. 5-30. If it is necessary to replace the klystron tube, the klystron cavity and frequency drive mechanism must be replaced as a unit. Replacement unit (HP Part No. 626A-95A) consists of a new klystron installed in c. Apply heat to component lead and remove lead with a straight upward pull. d. Remedy Use a toothpick or wooden splinter to cle an holes. Table 5-4. Pulse Section Troubleshooting Symptom Possible Cause Remedy No RF output with MOD SELECTOR set to INT or SQ WAVE. INT FM and CW positions satisfactory Defective V8, V9, or V10 Replace; see Table 5-5 Schmitt trigger sensitivity out of adjustment Adjust R44; see para 5- 43 No RF output with MOD SELECTOR set to INT and no SYNC OUT or DELAY SYNC OUT pulses. SQ WAVE position satisfactory Defective V11 Replace; see Table 5-5 No RF output with MOD SELECTOR set to INT and no DELAY SYNC OUT pulse. SYNC OUT pulse and SQ WAVE positions satisfactory Defective V12, V13, V14 Replace; see Table 5-5 Min. delay adj. misadjusted Adjust R78; see para 5-57 No RF output with MOD SELECTOR set to INT. SYNC OUT pulse, DELAY SYNC OUT pulse and SQ WAVE positions satisfactory Defective V15 Replace; seeTable 5-5 Min. width adj. misadjusted Adjust R85; see para 5-58 No RF output with MOD SELECTOR set to INT or SQ WAVE. SYNC OUT pulse, DELAY SYNC OUT pulse and INT FM and CW positions satisfactory Defective V18 Replace; see Table 5-5 5-5 TM 11-6625-2910-14 Model 626A Section V Table 5-5. Tube Complement Tube Type Function Adjustment Reference V1 6080 V2 V3 6AU6 OA2 V4 V5 V6 V7 V8 V9 6AU6 6AQ5 6AU6 5651 6AL5 12AT7 V10 V11 12AT7 2D21 Series Regulator (-300 volt supply and -400 volt supply) Control Tube(-300 volt supply) Voltage Reference Tube (-150 volts) PWR SET bridge supply Control Tube (-350 volt supply) Series Regulator (-550 volt supply) Control Tube (-550 volt supply) Reference Tube (- 550 volt supply) Clamping Diode Pulse Rate Multivibrator and Input Squaring Amplifier Schmitt Trigger Sync Out Thyratron V12 V13 V14 V15 V16 V17 VI8 6AL5 12AT7 2D21 12AT7 6X4 V39B 5687 Clamping Diode Pulse Delay Multivibrator Delayed Sync Out Thyratron Pulse Width Multivibrator Limiting Diode Klystron Oscillator Modulator a. a cavity which is attached to the associated frequency drive mechanism. A new calibrated frequency dial also included with the unit. Units are completely pre-tested and adjusted at the factory. Field installation of the replacement unit is simple and requires no extensive readjustment procedure. Units can be obtained from the factory on an exchange basis by contacting the nearest Hewlett-Packard field representative or factory service department. Table 5-2 Table 5-2 Paragraph 5-59 Table 5-2 Table 5-2 Table 5-2 Table 5-2 No adjustment required Paragraph 5-55 Paragraph 5- 43 No adjustment required; selection may be necessary, however. No adjustment required Paragraph 5-57 No adjustment required Paragraph 5-58 No adjustment required Paragraph 5-45 No adjustment required Rotate PWR SET maximum clockwise. b. In Figure 5-10, locate power set atten. drive in upper left hand corner of picture. Loosen allen setscrews that hold large gear in attenuator drive. c. Locate collar on attenuator drive shaft(parallel with panel) and gently pull this collar away from large attenuator drive gear until it stops. Power set attenuator card will now be clear of klystron cavity and you may proceed with klystron removal. CAUTION THE STOPS FOR THE FREQUENCY DRIVE MECHANISM ARE INOPERATIVE WHEN FREQUENCY DIAL IS NOT IN PLACE. ROTATING THE SHAFT FOR THE FREQUENCY DIAL AND FREQUENCY DRIVE CAM TO ONE EXTREME OR THE OTHERWITHOUT THESE STOPS MAY RESULT IN SERIOUS AND PERMANENT DAMAGE TO PLUNGERON INNER ENDOF FREQUENCYDRIVE ROD. HANDLE WITH CARE. d. After klystron assembly has been installed, slide attenuator shaft back toward large drive gear making sure setscrew on collar is on top. e. With PWR SET maximum clockwise, press large gear and collar together with your fingers and tighten setscrews on gear. f. Check operation of PWR SET to make sure it operates smoothly. 5-31. PRIOR TO REMOVAL. Before removing klystron cavity and frequency drive mechanism, the PW SET attenuator must be withdrawn from klystron cavity; failure to do this will result in a broken attenuator. To prevent damage to attenuator, proceed as follows: 5-32. REMOVAL. follows: a. tool. 5-6 Refer to Figure 5-3 and proceed as Obtain a scratch awl or similar sharp-pointed TM 11-6625-2910-14 Section V Model 626A Figure 5-3. View of Klystron Cavity and Frequency Drive Mechanism b. Rotate frequency control full counterclockwise to stop. Normally a small dot just to the left of 10 GHz. dial point will be under the hair line. i. Remove and save tubes V16 and V18. Note connections for the four wires from klystron cavity and disconnect at terminals adjacent to V16 tube socket. Remove and save frequency control knob and cover over frequency dial. This cover is held in place by four screws. j. Remove and save four screws holding waveguide section to klystron cavity. Support cavity as last screw is removed to prevent damage to waveguide. d. With awl, mark a valley on the frequency drive shaft gear and the tooth of frequency dial which meshes in this valley. k. Slide klystron cavity and frequency drive assembly to left and lift cavity upward. The entire assembly will now swing to one side to expose the connections to reflector mode switch. c. e. The dial is held on frequency dial shaft by a retaining ring with four screws. Remove all four screws without permitting frequency dial to rotate with respect to shaft and hub on which it is mounted. Place a short scratch mark across shaft end, dial hub, and a short way onto dial so that all three can be replaced later in exactly the same position. This scratch mark will be found on shaft, dial hub, and dial supplied in the replacement assembly (HP Part No. 626A-95A). f. m. Note connections to reflector mode switch by drawing a sketch before disconnecting leads. Disconnect leads. n. Lift entire assembly from instrument. Observe the CAUTION following para 5-30. 5-33. INSTALLATION. Refer toFigure5-3, and proceed as follows: Remove dial hub and spring washer over frequency dial shaft. Save spring washer for use in step f under paragraph 5-33, Installation. a. Reconnect leads to reflector mode switch. Refer to the sketch made in step m under paragraph 5-32, Removal. g. Note connections to reflector potentiometer by drawing a sketch before disconnecting leads. Disconnect leads. b. Swing klystron cavity and frequency drive mechanism in place on instrument and replace the four screws (removed in step j under Removal) that fasten klystron cavity to waveguide section. Tighten all screws firmly. h. Remove and save three front panel screws that hold frequency drive mechanism onto rear of panel. Tip instrument forward onto guard rail handles at each end of the panel. c. 5-7 Reconnect klystron leads. Refer to notes made in step I under Removal. Check connections carefully as an error may result in a burned out klystron. Replace tubes V16 and V18. TM 11-6625-2910-14 Section V Model 626A d. Hold frequency drive mechanism against back of front panel and turn instrument upright. Insert and tighten one of three screws (saved in step h under Removal) that hold frequency drive mechanism. Insert and tighten remaining two screws. e. Reconnect leads to reflector potentiometer. Refer to the sketch made in step g under Removal. f. Replace spring washer(saved in step f under Removal) over end of frequency dial shaft. g. Install frequency dial hub supplied with new assembly. Align scratch marks on end of shaft and dial hub, push hub back until end of shaft and surface of hub are approximately flush. Tighten setscrews in hub. The shaft must not protrude beyond the front surface of hub. h. Turn frequency drive shaft gear full counterclockwise. Replace frequency dial and align the mark on gear with the marked tooth on dial. Align scratch mark across dial hub and dial before replacing retaining ring and tightening the four screws. i. Replace frequency dial cover. J. Replace frequency control knob on frequency drive shaft. k. Rotate frequency drive shaft full counterclockwise and hold against stop. Check that the dot on frequency dial is under the hair line. 5-34. ADJUSTMENTS. After replacing the klystron cavity the following adjustments are necessary. Refer to Figure 5-3 and proceed as follows: a. Connect an ac voltmeter such as an HP Model 400D/H between the heater-cathode terminal and heater terminal. f. Set potentiometers R89 and R95 (Figure 5-10) to approximate center of range over which they can be rotated. These two controls are located on an insulated bracket mounted on the bottom edge of modulator assembly. g. Set frequency dial to 10 GHz and adjust control R92 for a voltmeter reading of * volts. Slowly increase frequency setting until the point is reached where reflector mode switch just operates as can be determined by an audible click. At this point adjust R87 for a voltmeter reading of * volts. If either R92 or R87 have insufficient range, adjust control R95 beyond point where desired reading is obtained and then readjust the particular control that originally had insufficient range. h. Decrease frequency dial setting slightly as required to cause reflector mode switch to operate. At this point, adjust control R88 for a voltmeter reading of * volts. Set frequency dial to 15. 5 GHz and adjust control R93 for a voltmeter reading of * volts. If either R88 or R93 have insufficient range, adjust control R89 beyond point where the desired reading is obtained and then readjust the particular control that originally had insufficient range. i. Repeat steps g and h several times as necessary. These controls all interact but if steps g and h are repeated enough times a point will be reached where additional adjustment will not be necessary. j. If reflector voltages are carefully set, no additional adjustments will normally be required. To check instrument performance refer to paragraph 5-62. 5-35. To better understand the relationship of parts in the klystron cavity and drive mechanism refer to Fig 5-4 and Fig 5-5. 5-36. REFLECTOR POTENTIOMETER REPLACEMENT. 5-37. To replace reflector potentiometer, R96, refer to Figure 5- 6 and proceed as follows: a. Remove power to instrument. b. Draw a sketch of reflector potentiometer, R96, noting color and location of leads. c. Remove leads from potentiometer. d. Remove retaining ring and back of potentiometer. Remove screw holding potentiometer to supporting bracket. e. Loosen setscrews on mode-switch cam located between cam and potentiometer. DO NOT LOOSEN setscrews between mode-switch cam and frequency drive casting (see Figure 5- 6). WARNING Use an insulated voltmeter. This is necessary due to high voltages applied to the klystron tube. If the voltmeter has a ground lead be sure it is isolated by using a three-prong to two-prong adapter and leave the pigtail floating. Extreme care must be taken to insulate the metal instrument case as it will be at the same potential as the ground clip lead. b. Connect power cord to proper source and turn Model 626A on. c. The heater voltage should be 6.3 Vac. If heater voltage is not 6.3 Vac refer to paragraph 5-39. d. Set Model 626A MOD SELECTOR switch to INT FM. e. Connect an HP Model 410B VTVM positive lead to the reflector terminal and negative or common lead to the cathode terminal. Voltmeter SELECTOR switch should be set to -. *These voltages vary from one klystron to another. Correct voltages will be specified in the instructions sent with each replacement unit. 5-8 TM 11-6625-2910-14 Section V Model 626A Figure 5-4. Cutaway Views of Klystron Cavity 5-9 TM 11-6625-2910-14 Section V Model 626A Figure 5-5. Exploded View of Klystron Cavity and Plunger Drive Mechanism f. Remove reflector potentiometer. g. Remove back from replacement potentiometer and connect it to supporting bracket with the screw removed in step d. h. Do not tighten mode -switch cam setscrews at this time. i. Refer to sketch made in step b and reconnect leads to potentiometer. j. Connect an ohmmeter set on the X1000 range between the center tap and wiper arm of potentiometer. k. Position frequency dial to point of mode- switch actuation. Move frequency dial back and forth through the mode- switch lag distance to determine mid-point. Place frequency dial at this mid-point. m. Hold frequency dial in place and adjust position of wiper arm inside potentiometer until ohmmeter reads minimum resistance. n. Tighten mode-switch cam setscrews and replace back of potentiometer. p. f necessary, perform reflector tracking adjustment as described in paragraph 5- 51k. b. Voltmeter reading should be 6.3 Vac. c. If voltmeter reads high, decrease shunt resistance (R131). Increase this resistance ff reading is low. Continue to change this resistance until the heater voltage reads 6.3 Vac. d. Wait 10 minutes and repeat steps a and b. If voltmeter reading is not 6.3 vac, repeat step c. 5-38. REPLACING RT1. 5- 39. After replacing RT 1 the klystron heater voltage should be checked and adjusted if necessary. Refer to Fig 5-2, Fig 5-3, and proceed as follows: a. Connect an ac voltmeter such as an HP Model 400D/H between the heater-cathode terminal and heater terminal. Figure 5-6. Detail Showing Reflector Potentiometer Removal 5-10 TM 11-6625-2910-14 Section V Model 26A d. Adjust oscilloscope so that it is calibrated to 1 µsec/cm. e. Adjust R44 until pulse duration is 5 µsec. 5-40. ADJUSTMENTS. 5-41. ZERO SET CONTROL ADJUSTMENT. 5-42. When front panel ZERO SET control will not zeroset the power-monitor meter, the range of this control needs to be extended. To extend its range, refer to Figure 5-7 and proceed as follows: a. Set MOD SELECTOR to OFF and position ZERO SET control to its mechanical center. b. Adjust R98 until power- monitor meter indicates Zero Set. 5-45. ADJUSTMENTS FOLLOWING KLYSTRON REPLACEMENT. 5-46. Following replacement of a new klystron (tube only) certain adjustments must be made before the instrument will operate in a satisfactory manner. The general steps in the overall procedure are as follows: a. Establish initial reflector tracking voltages. 5-43. SCHMITT TRIGGER LEVEL ADJUSTMENT. b. Partial reset of frequency dial. 5- 44. To adjust schmitt trigger level, refer to Figures 5-2, 5-10, and proceed as follows: a. Connect test setup as shown in Figure 5-8. Oscilloscope vertical input is to be connected to terminal B GRN on modulator board. c. Suppress undesired modes of oscillation, fineadjust frequency dial and fine-adjust reflector tracking. d. Output power response adjustment. b. Adjust calibrated pulse generator outputfor4000 pps. Pulses should be 5 µsec duration and 5 volts peak. For maximum accuracy, calibrate pulse generator with oscilloscope. c. Set Model 626A MOD SELECTOR to OFF and TM 11-6625-2910-14 5-47. INITIAL REFLECTOR-VOLTAGE ADJUSTMENTS. a. Check all power supply voltages as indicated in Table 5-2. b. Reflector voltages can now be set, as described in paragraph 5-49, to values given on the data sheet Figure 5-7. Right Side View Showing Power Monitoring Bridge Adjustment 5-11 Model Section V Figure 5-8. Test Setup for Observing Reflector Modes supplied with the replacement klystron. Voltages are most easily measured at klystron terminal strip located on the modulator deck. There arefour terminals marked K, H, H, R. Cathode-to-reflector voltage is measured between terminals K and R. The frequency at which each reflector tracking potentiometer is adjusted is shown in Figure 5-9. WARNING When measuring reflector-to-cathode voltage the reflector should be negative with respect to the cathode by the voltage shown in the data sheet. Use extreme care when measuring this voltage since it is 1200 volts negative with respect to instrument chassis. Note A data sheet supplied with the replacemen klystron tabulates reflector (reflector-to cathode) voltage vs frequency. The klystroi manufacturer tests the tube under slightly different operating conditions from those in the instrument, but voltages are close enough to be useful when making tracking adjustments It should be mentioned that while voltages given at 10 GHz and 15.5 GHz are directly applicable, the klystron manufacturer switches from 3-3/4 reflector mode to4-3/4 reflector at a frequency (generally 13.5 GHz) which varies slightly from that at which the instrument switches (generally 12.8GHz). Voltages specified in the data sheet should be used however, and (R87 or R88) adjusted above and below the instrument mode switching point. (This is proper practice since adjustment pots are designed to adjust voltages at the high and low frequency sides of specific modes rather than at specific frequencies.) The setting obtained this way will be close enough for initial tracking. Figure 5-9. Graph Showing Reflector Tracking Voltage vs Frequency 5-48. INITIAL TRACKING PROCEDURE. Refer to Figure 5-10 and proceed as follows: 5-12 TM 11-6625-2910-14 Section V Model 626A a.SetR95 and R89 to mechanical center of rotation. f.When voltages are correct, remove power from instrument and connect klystron heater and cathode leads as shown in Figure 5-4a. 5-49. INITIAL FREQUENCY SETTING. a.Turn Model 626A on and check klystron heater voltage (paragraph 5- 39). b.Set Model 626A controls as follows: b.Connect voltmeter common to klystron terminal K, and connect positive lead to klystron terminal R. Set frequency dial to 10GHz and adjust R92 (and R95if necessary) to read tabulated voltage for 10 GHz point. c.Set frequency dial to point near 12. 8 GHz just before microswitch actuates. Adjust R88 (and R89 if necessary) to read tabulated voltage for 3- 3/4 reflector mode high frequency point. d.Set frequency dial to point near 12.8 GHz just after microswitch actuates. Adjust R87 to read tabulated voltage for low frequency point of 4- 3/4 reflector mode. e.Set frequency dial to 15.5 GHz and adjust R93 to read tabulated voltage for 15. 5-GHz point. MOD SELECTOR ................................................ INT FM OUTPUT ATTEN .............................................. +10 DBM FM AMPLITUDE ......................................... full clockwise frequency dial ................................................... 15.5 GHz c.Connect test setup as shown in Figure 5-11, and check for output. Figure 5-10. Top View Showing Location of Reflector Tracking Pots 5-13 TM 11-6625-2910-14 Section V Model 626A Figure 5-11. Test Setup for Observing Reflector Modes Note The test setup shown in figure 5-11 with control settings on the signal generator described in step b permits the Model 626A to internally FM the klystron with a 60- Hz sine wave of sufficient amplitude to drive the klystron in and out of oscillation (see paragraph 3- 13). When an oscilloscope is connected, its horizontal sweep circuit is driven by 60 Hz synchronized with the 60-Hz sine wave frequency modulating the reflector. Vertical trace is driven by detected output from klystron. As klystron passes in and out of oscillation a humped waveform will appear on the oscilloscope. The hump is an indication of klystron output amplitude vs reflector voltage and may be construed as the reflector mode for frequency of oscillation. Typical mode pattern oscillograms appear in Figure 5-12. e. Adjust FM PFASE for optimum presentation of mode pattern at 15.5 CHz. It may be necessary to bring crest of the mode pattern closer to the oscilloscope vertical centerline with R93 in order to produce satisfactory output, but such a tracking adjustment is not critical at this stage of alignment as long as significant output is available at extremes of the band. If voltages have been set according to klystron manufacturer’s data sheet, adequate output should be available, barring such considerations as a weak klystron or improper seating in cavity. f. Set frequency dial near high frequency end. Where plunger rod is accessible, loosen setscrews holding plunger rod to cam follower (refer to Figure 5-5). WARNING d. Adjust oscilloscope to center horizontal trace for equal deflection on each side of vertical scale center. When loosening setscrews holding plunger rod to cam follower, extreme care should be used as microswitch (located near cam follower) has high negative voltages on it. 5-14 TM 11-6625-2910-14 Section V Model 626A g. Pull plunger rod out of cavity until it hits frequency drive cam. Tighten lightly side setscrew holding plunger rod to cam follower. pattern, proceed with paragraph 5-50. If notch is not present, proceed with step m. m. Loosen setscrews on frequency drive cam. Hold frequency dial in position and adjust the cam (thus moving cam follower, plunger rod, and plunger) until wavemeter notch appears on mode pattern. Tighten setscrews on frequency drive cam. h. Set frequency dial to 15.5 GHz (changing wavemeters and detector mounts if necessary) and set wavemeter to 15.5GHz. Loosen setscrew holding plunger rod. i. With a thin-pointed tool, push plunger rods lightly into the cavity until wavemeter notch appears on mode pattern. Tighten one setscrew lightly which holds plunger rod to cam follower. 5- 50. MODE SUPPRESSION AND REFLECTOR TRACKING. Mode suppression in Model 626A consists of reducing effects of the 1/4 wave cavity mode and, in case of vigorous tubes, the 5/4 wave cavity mode. These unwanted modes create most problems around the 12.8 GHz mode switch point and it is here that suppression is conducted. Note The purpose of adjustments in step i (adjusting plunger rod) and in step m (adjusting cam) is to adjust the length of plunger travel against length of dial travel from the low end of the band to high end of the band. These adjustments interact, but by repeated adjustments of the cam at 10 GHz and plunger rod at 15.5 GHz, the ends of the dial may be brought into calibration. DO NOT loosen frequency dial hub-screws or otherwise attempt to calibrate the dial by slipping it at the hub. 5-51. Unwanted modes are suppressed before fine reflector tracking adjustments are made, and in rare cases the fine tracking adjustments may interact with the 1/4 wave cavity mode suppression. When this happens the 1/4 wave mode suppressor can be adjusted slightly to restore adequate suppression. Trouble with the 5/4 wave cavity mode is remote; however, proper techniques for suppressing both unwanted modes are described. a. Connect test setup as shown in Figure 5-11. j. Repeat steps e through h to obtain approximate dial calibration at the end of the band. Final calibration is made between mode suppression and fine tracking adjustments. k. Set 10 GHz on wavemeter and also on Model 626A freuencv dial. If wavemeter notch is resent on mode b. Set frequency to the high frequency side of mode switching point and look for evidence of the 1/4 wave cavity mode. At this point on the frequency dial the 1/4 wave mode will appear ont he high frequency(high Figure 5-12. Typical Mode Patterns 5-15 TM 11-6625-2910-14 Section V Model 626A voltage) side of the desired mode. Under worst conditions two similar modes can be present. Modes can be identified with a wavemeter if doubt exists as to which side of the modes is the high frequency (high voltage) side. WARNING To reach the 1/4 wave suppressor matching screw the tool must pass between klystron heater and cathode connections. USE CARE due to high negative voltages at these points. The best way to use the special tool is to insert the fiber tube (suppressor locknut wrench) first; then insert the metal suppressor wrench through the fiber tube to adjust the suppressor. Lock down the suppressor matching screw when adjustment is completed. Remove metal wrench, then remove fiber wrench. Note Desired and undesired modes are most easily identified by using a wavemeter. Frequency of the 1/4 wave cavity mode will be from 9.7 to 10.7 GHz while that of the desired mode will correspond closely to that shown on the frequency dial, approximately 12 to 13 GHz. Frequency of the 5/4 wave cavity mode will probably be above 15.5 GHz. d. Tune up the band to 15. 5 GHz observing oscilloscope pattern as you go. At higher frequencies the ¼ wave mode may reappear, but it will be on the low frequency side of the desired mode at these frequencies and will cause no interference. If actual interference c. Adjust the 1/4 wave mode suppressor matching screw to eliminate interference. Use the special fiber tool supplied with the instrument and refer to Figure 5-13. Figure 5-13. Adjustment of Mode Suppressors and Output Matching Screw 5-16 TM 11-6625-2910-14 Section V Model 626A Figure 5-14. Calibration Test Setup occurs between 12.8 and 15. 5 GHz, readjust 1/4 wave mode suppressor matching screw. frequency side into the mode. Verify high frequency side, if necessary, with wavemeter. e. Tune the frequency dial across the low end of the band from stop to mode switch point. The 5/4 wave mode, if present, will normally appear somewhere below 10. Z GHz. Its presence is revealed as a slight outward bulge on the high frequency side of the desired mode at the base line as shown in Figure 5-12c. Note When MOD SELECTOR is placed in OFF position, voltage applied to reflector should bias the klystron off. If mode pattern is centered on oscilloscope the reflector voltage may not be adequate to bias the klystron off. Pulse and square- wave operation may be deteriorated by failure of klystron to cut off during "off" portion of modulation. If mode pattern is positioned so that the high frequency side is too close to oscilloscope vertical centerline, a weak output is obtained. f. To suppress this mode, adjust the 5/4 wave mode suppressor shown in Figure 5-13. Another special tool is provided to assist you in this adjustment; it is the small hollow spanner wrench secured inside the chassis. After unthreading lockscrew insert a No. 10allen wrench through it to adjust suppressor. After achieving the desired suppression, lock suppressor in place. m. Set frequency dial to point just before microswitch actuation and adjust mode pattern with R87 as described in step k. g. Check across entire frequency band to make sure that all mode suppression is effective. h. Perform paragraph 5- 49, steps f through m, except dial should be set to within 100 MHz of 10 GHz and within 155 MHz of 15. 5 GHz. C heck points between 10 15.5 GHz. If these points are out of specifications (1%) a compromise of the extremes will correct the dial. i. n. Set frequency dial to point just past microswitch actuation and adjust mode pattern with R87 as described in step k. p. Set frequency dial to 15.5 GHz and adjust mode tern with R93 as described in step k. After final dial calibration tighten all setscrews. q. Since adjustments are somewhat interacting, tune through frequency range of Model 626A observing tracking behavior. Readjust pots as necessary to produce satisfactory tracking. j. Once undesired modes have been suppressed and final dial calibration performed, the reflector tracking must be fine-adjusted. Center the oscilloscope horizontal trace. 5-52. TRACKING CHECK, PULSE AND SQUARE WAVE. k. Set frequency dial to 10 GHz and adjust R92 so that the vertical centerline of oscilloscope graticule divides the mode pattern about 1/3 of the way from the high a. Connect test setup as shown in Figure 5-14. 5-17 TM 11-6625-2910-14 Section V Model 626A Figure 5-15. Typical Pulse and Square Wave Oscillograms b. Set Model 626A controls as follows: SYNC SELECTOR .................................. X10 MOD SELECTOR.................................... INT PULSE RATE .......................................... 100 PULSE DELAY........................................ 3 µsec PULSE WIDTH........................................ 1 µsec c. a. Connect test setup as shown in Figure 5-16. b. Set signal generator frequency dial to 10 GHz and PWR SET for maximum output power as indicated on Model 430C. Record reading obtained. c. Set signal generator frequency dial to 15.5 GHz and record reading obtained. Adjust oscilloscope for a 1 µsec/cm sweep. d. Adjust output matching screw for a reading approximately midway between readings obtained in steps band c. This adjustment is interacting so repeat it at 10 and 15. 5 GHz until maximum output power is approximately equal at both ends of frequency band. d. Tune frequency dial on signal generator slowly from 10tol5. 5GHzwhile observing pulse shape and pulse base line appearance on oscilloscope. Various pulse waveforms are shown in Figure 5-15. If pulses have sharp overshoot, the reflector tracking potentiometer for that frequency has been adjusted beyond the crest of the mode pattern. A ragged base line indicates that oscillation is taking place when klystron should be cut off. If either of these troubles are present, readjust tracking potentiometer applicable to reflector mode and frequency under examination. e. Check across frequency band to see that power monitor meter can be POWER SET. 5-54. CALIBRATION. 5-55. CALIBRATING PULSE RATE DIAL. 5-56. Replacing V9 may change calibration of the pulse rate dial but will not otherwise affect the signal generator performance. If the replacement tube triode sections are too far out of balance, try another tube. Recalibration procedure is as follows: a. Connect test setup as shown in Figure 5-14 DELAYED SYNC OUT signal may be used instead of the RF pulse. e. Set MOD SELECTOR to OFF and PWR SET to full clockwise position. Tune across the band while observing power-monitor meter for any indication of RF power. Where power is present the reflector tracking voltage for the particular frequency is not properly adjusted and does not bias klystron out of oscillation mode. Adjust appropriate tracking potentiometer to eliminate indication. b. In series with the output of a calibrated audio oscillator, connect a 10K resistor and then connect the oscillator to the vertical input of oscilloscope. 5-53. OUTPUT POWER RESPONSE ADJUSTMENT. After satisfactory tracking has 4een obtained and undesired modes suppressed, the output matching screw must be adjusted as shown in Figure 5-13. c. Zero-s et and power-set the power-monitor meter. Refer to para 3-9b and para 3-9c. 5-18 TM 11-6625-2910-14 Section V Model 626A d. Set Model 626A controls as follows: MOD SELECTOR.................................................. INT SYNC SELECTOR ................................................ X10 PULSE RATE ........................................................ 100 e. Set audio oscillator frequency to 1000 Hz. f. Adjust PULSE RATE until sync pulses zero-beat with signal from audio oscillator. g. Without changing PULSE RATE control position, slip dial so that 100 is located under index on front panel. h. Check PULSE RATE dial calibration at 40 and 400. If dial is in error, slip dial to average error across range. 5-57. CALIBRATING PULSE DELAY DIAL. a. Connect test setup as shown in Figure 5-14. b. Zero-set and power-set the power-monitor meter. Refer to para 3-9b and para 3-9c. c. Set Model 626A controls as follows: MOD SELECTOR.......................................... NT SYNC SELECTOR ........................................ X1 or X10 PULSE DELAY .............................................. minimum d. Adjust R78 (Figure 5-2) so that delay between SYNC OUT(start of horizontal trace) and leading edge of RF pulse is <3 microseconds on calibrated oscilloscope. e. Set PULSE DELAY so that 50 microseconds delay exists between SYNC OUT and leading edge of RF pulse. f. Without changing PULSE RATE control position, slip dial so that 50 is located under index on front panel. g. Check PULSE DELAY dial calibration at 5 and 200. If necessary repeat steps c through f. 5-58. CALIBRATING PULSE WIDTH DIAL. a. Connect test setup as shown in Figure 5-14 except that DELAYED SYNC OUT signal is to be used for triggering oscilloscope. b. Zero-set and power-set the power-monitor meter. Refer to para 3-9b and para 3-9c. c. Set Model 626A MOD SELECTOR to INT and PULSE WIDTH to minimum. d. Adjust R85(Figure 5-2) for a pulse width of just less than 0.5 microseconds as observed on a calibrated oscilloscope. e. Locate within frequency band of generator the point of maximum pulse width. f. At frequency of maximum pulse width, readjust R85 for a pulse width of just less than 0.5 microseconds. g. Set PULSE WIDTH for a 10-microsecond pulse as observed on calibrated oscilloscope. h. Without changing PULSE WIDTH control position, slip dial so that 10 is located under index on front panel. 5-59. POWER- MONITOR METER CALIBRATION. 5-60. Replacement of power-set monitoring thermistor (RT123) requires considerable skill and equipment. If facilities are not available consult your Hewlett-Packard field sales engineer or write Customer Service Department at the factory concerning repair. 5-61. If facilities are available, and the replacement is to be made in the field, the entire thermistor mount may be procured as a unit under HP Stock No. 626A-28 Figure 5-16. Test Setup for Adjusting Output Power 5-19 TM 11-6625-2910-14 Section V Model 626A Recalibration procedure for the power- monitor meter is as follows: a. Connect test setup as shown in Figure 5-16. g. Set signal generator frequency dial to 12.5 GHz, and repeat steps c through f. Frequency meter should read 12.5 GHz ±125 MHz. h. Remove M-band equipment from test setup, and replace with P-band equipment using the Model MP292B Adapter. Adapter is to be connected between frequency meter and RF OUTPUT of signal generator. i. Set signal generator frequencydialtol5.5GHz, and repeat steps c through f. Frequency meter should read 15.5 GHz ±155 MHz. 5-65. OUTPUT POWER CHECK. a. Connect test setup as shown inFigure5-16 using P-band equipment and the Model MP292B Adapter. b. Using a calibrated frequency meter, set signal generator output for 15.5 GHz. c. Zero-set and power-set the power-monitor meter. Refer to paragraphs 3-9b and 3-9c. d. Set MOD SELECTOR to OFF and OUTPUT ATTEN to -1 dBm. e. Zero-set a power meter such as a Model 430C as per its instruction manual, and set RANGE switch to 0 dBm. f. Set signal generator MOD SELECTOR to CW. g. With Model 430C properly zero-set, the meter should read - 1 dBm + 1 dB. h. Repeat steps b through g except set signal generator output for 12.5 GHz. i. Remove P-band equipment and adapter from test setup and replace with M-band equipment. j. Repeat steps b through g except set signal generator output for 10 GHz. b. Set Model 626A MOD SELECTOR to CW and frequency dial to center of band (12.75GHz). c. Set OUTPUT ATTEN to- 2 dBm and adjust PWR SET for a - 2 dBm reading on Model 430C. d. Adjust R108 (Figure 5-7) so that power-monitor meter indicates 0 dBm (red line at center of scale). Note To increase accuracy of power output calibration at a particular frequency follow the above procedure at that frequency. 5-62. PERFORMANCE CHECKS. 5-63. Performance checks are included to verify proper operation of the Model 626A. They may be used by incoming quality control for the electrical inspection. 5-64. FREQUENCY CALIBRATION CHECK. a. Connect test setup as shown in Figure 5-16 using M- band equipment. b. Set signal generator frequency dial to 10 GHz. c. Zero-set and power-set the power-monitor meter. Refer to para 3-9b and para 3-9c. d. Set MOD SELECTOR to CW and OUTPUTATTEN to 0 dBm. e. Adjust power meter to read 0 dBm(1 mW). f. Adjust frequency meter to locate a dip in power around the frequency output of signal generator. Frequency meter should read 10 GHz ±100 MHz. 5-20/21 TM 11-6625-2910-14 Model 626A Section V Figure 5-17. Power Supply, Voltage and Resistance Diagram 5-22 TM 11-6625-2910-14 Section V Model 626A Figure 5-18. Power Supply 5-23 TM 11-6625-2910-14 Model 626A Section V Figure 5-19. Pulse Section, Voltage and Resistance Diagram 5-24 TM 11-6625-2910-14 Model 626A Section V Figure 5-20. Pulse Generator 5-25 TM 11-6625-2910-14 Section V Model 626A Figure 5-21. Modulator and RF Generator Sections, Voltage and Resistance Diagram 5-26 TM 11-6625-2910-14 Model 626A Section V Figure 5-22. Modulator and RF Generator 5-27/5-28 TM 11-6625-2910-14 Section V Model 626A SECTION VI REPLACEABLE PARTS 6-1. INTRODUCTION. 6-2. This section contains information for ordering replacement parts. Table 6-1 lists parts in alphanumerical order of their reference designators and indicates the description and stock number of each part, together with any applicable notes. Table 6-2 lists parts in alpha- numerical order of their stock numbers and provides the following information or each part: a. Description of the part (see list of abbreviations below). b. Typical manufacturer of the part in a five-digit code; see list of manufacturers in appendix. c. Manufacturer’s stock number. d. Total quantity used in the instrument (TQ col.) e. Recommended spare part quantity for complete maintenance during one year of isolated service (RS column). 6-3. Miscellaneous parts not indexed in table 6-1are listed at the end of Table 6-2. A B C CR DL DS E a = = = = = = = assembly motor capacitor diode delay line device signaling (lamp) misc electronic part = amperes bp bwo = bandpass = backward wave oscillator c = carbon cer = ceramic cmo = cabinet mount only coef = coefficient com = common comp = composition conn = connection crt = cathode-ray tube dep = deposited EIA = Tubes or transistors meeting Electronic Industries’ Association standards will normally result in instrument operating within specifications; tubes and transistors selected for best performance will be supplied if ordered by HP stock numbers. 6-4. ORDERING INFORMATION. 6-5. To order a replacement part, address order or inquiry either to your authorized Hewlett- Packard sales representative or to CUSTOMER SERVICE Hewlett- Packard Company 333 Logue Avenue Mountain View, California or, in Western Europe, to Hewlett- Packard S. A. 1217 Meyrin Geneva, Switzerland 6-6. Specify the following information for each part: a. Model and complete serial number of instrument. b. Hewlett-Packard stock number. c. Circuit reference designator. d. Description. 6-7. Toordera part notlisted in Table 6-1 and Table 6-2. givea complete description of the part and include its function and location. elect encap REFERENCE DESIGNATORS fuse P = plug filter Q = transistor jack R = resistor relay RT = thermistor inductor RT = thermistor meter S = switch mechanical part T = transformer ABBREVIATIONS = electrolytic mtg = mounting = encapsulated my = mylar f fxd = farads = fixed Ge grd = germanium = ground(ed) h Hg = henries = mercury nsr impg incd ins = impregnated = incandescent = insulation(ed) obd K = kilo = 1000 lin log = linear taper = logarithmic taper m M ma µ minat mfgl Mfr = = = = = = = F FL J K L M MP = = = = = = = -3 milli = 10 megohms milliamperes -6 micro - 10 miniature metal film on glass manufacturer NC Ne NO NPO p pc = = = = normally closed neon normally open negative positive zero (zero temperature coefficient) = not separately replaceable = order by description pos poly pot = peak = printed circuit board = picofarads = -12 10 farads = peak-to-peak = peak inverse voltage = position(s) = polystyrene = potentiometer rect = rectifier pf pp piv 6-1 V = vacuum tube, neon bulb, photocell, etc. W = cable X = socket XF = fuseholder XDS = lampholder Z = network rot rms rmo = rotary = root-mean-square = rack mount only s-b Se sect Si sil sl td TiO2 = = = = = = = = slow-blow selenium section(s) silicon silver slide time delay titanium dioxide tog tol trim twt = = = = toggle tolerance trimmer traveling wave tube var w/ W ww w/o * = = = = = = variable with watts wirewound without optimum value selected at factory, average value shown(part may be omitted) TM 11-6625-2910-14 Section VI Model 626A Table 6-1. Reference Designation Index Circuit Reference HP Stock No. AT1 Description # PWR SET attenuator assembly (not field replaceable) RF attenuator assembly (not field replaceable) AT2 B1 3140-0052 3160-0012 Motor, fan Blade, fan C1 C2, 3 C4, 5 C6, 7 C8 0180-0019 C: fxd, elect, 451µf -10% +50%, 450 vdcw Not Assigned C: fxd, cer, 0.01µf ±20%, 1000 vdcw C: fxd, elect, 45µf -10%+50%, 450 vdcw C: fxd, cer, 0.01µf +20%, 1000 vdcw C9A,B 0160-0089 C10, 11 C12 C13, 14 C15 0180-0019 0150-0012 0140-0028 C: fxd, paper, 2 sect., 0.1µf/sect, -10% +20%, 1000 vdcw C: fxd, elect, 45µf -10% +50%, 450 vdcw C: fxd, cer, 0.01µf ±20%, 1000 vdcw Not Assigned C: fxd, mica, 560pf ±10%, 500 vdcw C16 C17 C18, 19 C20 C21 0140-0071 0160-0050 0150-0011 0140-0071 0140-0028 C: fxd, sil mica, 5600pf ±10%, 500 vdcw C: fxd, paper, 0.1µf ±10%, 400 vdcw C: fxd, TiO2, 1.5pf ±20%, 500 vdcw C: fxd, sil mica, 5600pf ±10%, 500 vdcw C: fxd, mica, 560pf ±10%, 500 vdcw C22 C23 C24 C25 C26 0160-0050 0150-0012 0140-0035 0140-0032 0140-0044 C: fxd, paper, 0.1µf +10%, 400 vdcw C: fxd, cer, 0.0µf ±20%, 1000 vdcw C: fxd, mica, 39pf ±5%, 500 vdcw C: fxd, mica, 47pf ±10%, 500 vdcw C: fxd, mica, 560pf +10% C27 C28 C29 C30 C31 0140-0041 0160-0050 0140-0031 0140-0044 0150-0012 C: fxd, mica, 100pf ±10%, 500 vdcw C: fxd, paper, 0.1µf ±10%, 400 vdcw C: fxd, mica, 220pf ±10%, 500 vdcw C: fd, mica, 560pf ±10% C: fxd, cer, 0.01pf ±20%, 1000 vdcw C32 C33, 34, C35 C36 0140-0041 0160-0050 0160-3192 0160-0088 C: fxd, mica, 100pf ±10%, 500 vdcw C: fxd, paper, 0.1µf ±10%, 400 vdcw C: fxd, paper, 0.1pf ±10%, 1200 vdcw C: fxd, paper, 0.25µf ±10%, 1500, vdcw 0150-0012 0180-0019 0150-0012 # See introduction to this section 6-2 Note TM 11-6625-2910-14 Section VI Model 626A Table 6-1. Reference Designation Index (Cont’d) Circuit Reference HP Stock No. Description # C: fxd, paper, 2 sect., 0.1µf/sect, -10% ±20%, 1000 vdcw C: fxd, mica, 470pf ±10%, 500 vdcw C: fxd, paper, 1µf ±10%, 600 vdcw C: fxd, cer, 0.1µf ±20%,1000 vdcw C: fxd, mica, 680pf ±10%, 500 vdcw C37A, B 0160-0089 C38 C39 C40 C41 0140-0027 0160-0079 0170-0055 0140-0007 C42, 43 C44 C45 C46A/B, 47A/B C48 0150-0012 0140-0021 0180-0125 0140-0021 C: fxd, cer, 0.01µf ±20%, 1000 vdcw Not Assigned C: fxd, mica, 39pf ±10%, 500 vdcw C: fxd, elect, 4 sect., 205µf/sect, 450 vdcw C: fxd, mica, 39pf ±10%, 500 vdcw CR1 CR2 thru CR15 DS1 F1 1910-0016 1901-0029 2140-0244 2110-0055 Diode, Ge Diode, Si Lamp: Glow Fuse, cartridge: 4amp,(For 115 V operation) 2110-0002 Fuse, cartridge: 2 amp, For 230 V operation) J1 J2 J3 thru J6 J7 J8 thru J10 1251-2357 1251-0007 1200-0005 1250-0035 1250-0075 Connector: AC Receptacle 3 pin male Connector, female: 16 contact Socket, tube: octal Socket, tube Connector: BNC panel jack J11 1250-0074 Connector, female: BNC K1 0490-0009 L1 L2 L3 L4 L5 9110-0011 9140-0022 9140-0019 9140-0020 9140-0021 Reactor, filter: 6 h Inductor, RF: 500 µh Inductor, RF: 200 µh Inductor, RF: 400 µh Inductor, RF: 430 µh L6 9140-0019 Inductor, RF: 200 µh M1 1120-0037 Meter, PWR SET Relay: time delay, SPST # See introduction to this section 6-3 Note TM 11-6625-2910-14 Section VI Model 626A Table 6-1. Reference Designation Index (Cont’d) Circuit Reference HP Stock No. Description # P1 P2 P3 thru P6 P7 8120-1348 1251-0006 1251-0026 1251-0052 Power cable: Detachable Connector, male: 16 contact Connector, male: octal Connector, male: 11 pin R1 R2 R3 R4 R5 R6 R7 R8 R9 R10, 11 0816-0006 0687-1551 0687-1051 0687-6831 0730-0096 0693-3331 0815-0003 0816-0006 0690-1051 R: fxd, ww, 5K ohms ±10%, 10 W R: fxd, comp, 1.5M ±10%, 1/2 W R: fxd, comp, 1M ±10%, 1/2 W R: fxd, comp, 68K ohms ±10%, 1/2 W R: fxd, dep c, 683.7K ohms ±1%, 1 W Not Assigned R: fxd, comp, 33K ohms ±10%, 2 W R: fxd, ww, 4K ohms ±5%, 10 W R: fxd, ww, 5K ohms ±10%, 10 W R: fxd, comp, 1M ±10%, 1 W R12 R13 R14 R15 R16 0690-5641 0693-3341 0686-3635 0730-0103 0727-0253 R: fxd, comp, 560K ohms ±10%, 1 W R: fxd, comp, 330K ohms ±10%, 2 W R: fxd, comp, 36K ohms ±5%, 1/2 W R: fxd, dep c, 900K ohms ±1%, 1 W R: fxd, dep c, 750K ohms ±1%, 1/2 W R17 R18 R19, 20 R21 R22 0690-1001 0690-1051 0690-3341 0693-1541 Not Assigned R: fxd, comp, 10 ohms ±10%, 1 W R: fxd, comp, 1M ±10%, 1 W R: fxd, comp, 330K ohms ±10%, 1 W R: fxd, comp, 150K ohms ±10%, 2 W R23 R24 R25, 26 R27 R28 0690-1041 0687-3931 0690-2241 0730-0092 2100-0098 R: fxd, comp, 100K ohms ±10%, 1 W R: fxd, comp, 39K ohms ±10%, 1/2 W R: fxd, comp, 220K ohms ±10%, 1 W R: Xfd, dep c, 490K ohms ±1%, 1 W R: var, comp, lin, 20K ohms ±20% R29 R30 R31 R32, 33 R34 0730-0062 0730-0093 0690-1001 0687-1011 2100-0034 R: fxd, dep c, 80K ohms ±1%, 1 W R: fxd, dep c, 516K ohms ±1%, 1W R: fxd, comp, 10 ohms ±10%, 1 W R: fxd, comp, 100 ohms ±10%, 1/2 W R: var, comp, lin; 250K ohms ,±10% # See introduction to this section Note 6-4 TM 11-6625-2910-14 Section VI Model 626A Table 6-1. Reference Designation Index (Cont’d) Circuit Reference HP Stock No. Description # R35 R36 R37, 38 R39, 40 R41* 0686-1555 0687-1051 0687-2241 0690-1031 0777-0002 R: fxd, comp, 1. 5M ±5%, 1/2 W R: fxd, comp, 1M ±10%, 1/2 W R: fxd, comp, 220K ohms ±10%, 1/2 W R: fxd, comp, 10K ohms ±10%, 1 W R: fxd, mfgl, 75K ohms ±5%, 7 W (Factory Selected Part, Typical Value Given) R42 R43 R44 R45 R46 0686-1555 0730-0110 2100-0096 0730-0087 0727-0252 R: fxd, comp, 1.5M ±5%, 1/2 W R: fxd, dep c, 1. 63M ±1%, 1W R: var, comp, lin, 1M ±30%, 1/4 W R: fxd, dep c, 370K ohms ±1%, 1 W R: fxd, dep c, 740K ohms ±1%, 1/2 W R47 R48 R49 R50 R51 R52 R53 R54 R55 R56 R57 0687-1031 0687-3321 0770-0004 0727-0223 0693-6821 0730-0080 0730-0082 0687-4731 0690-1221 0687-1521 0687-1541 R: fxd, comp, 10K ohms ±10%, 1 W R: fxd, comp, 3.3K ohms ±10%, 1/2 W R: fxd, mfgl, 10K ohms ±5%, 4 W R: fxd, dep c, 216.3K ohms ±19%b, 1/2 W R: fxd, comp, 6. 8K ohms ±10%, 2 W R: fxd, dep c, 245K ohms, ± 19, 1W R: fxd, dep c, 265K ohms ± 1%, 1W R: fxd, comp, 47K ohms ±10%, 1/2 W R: fxd, comp, 1. 2K ohms ±10%, 1 W R: fxd, comp, 1.5K ohms ±10%, 1/2 W R: fKd, comp, 150K ohms ±10%, 1/2 W R58 R60 R61 R62 R63 0687-1041 0687-3951 0687-8211 0693-1531 0690-1031 R: fxd, comp, 100K ohms ±10%, 1/2 W R: fxd, comp, 3.9M ±10%, 1/2 W R: fxd, comp, 820 ohms ±10%, 1/2 W R: fxd, comp, 15K ohms ±10%, 2 W R: fxd, comp, 10K ohms ±10%, 1 W R64 R65 R66 R68 R69 0777-0002 0690-4751 0687-1041 0687-1541 0687-5631 R: fxd, mfgl, 75K ohms ±5%, 7 W R: fxd, comp, 4.7M ±10%, 1 W R: fxd, comp, 100K ohms ±10%, 1/2 W R: fxd, comp, 150K ohms ±10%, 1/2 W R: fxd, comp, 56K ohms ±10%, 1/2 W R70 R71, 72 R73 R74 R75 0687-2251 0687-1221 0687-1521 0693-1231 0687-3921 R: fxd, comp, 2. 2M ±10%, 1/2 W R: fxd, comp, 1.2K ohms ±10%, 1/2 W R: fxd, comp, 1.5K ohms ±10%, 1/2 W R: fxd, comp, 12K ohms ±10%, 2 W R: fxd, comp, 3.9K ohms ±10%, 1/2 W # See introduction to this section 6-5 Note TM 11-6625-2910-14 Section VI Model 626A Table 6-1. Reference Designation Index (Cont’d) Circuit Reference HP Stock No. Description # R76 R77 R78 R79 R80 0687-1041 0777-0002 2100-0096 0687-4741 2100-0014 R: fxd, comp, 100K ohms ±10%, 1/2 W R: fd, mfgl, 75K ohms ±5%, 7 W R: var, comp, lin, 1M ±30%, 1/4 W R: fxd, comp, 470K ohms ±10%, 1/2 W R: var, comp, 220K ohms ±20% R81, 82 R83 R84 R85 R86 0687-2731 2100-0014 0687-3941 2100-0096 0690-2231 R: fxd, comp, 27K ohms ±10%, 1/2 W R: var. comp, 220K ohms ±20% R: ixd, comp, 390Kohms ±10%, 1/2 W R: var, comp, lin, 1M ±30%, 1/4 W R: fxd, comp, 22K ohms ±10%, 1 W R87 R88, 89 R90 R91 R92, 93 2100-0045 2100-0028 0690-1031 06904821 2100-0028 R: var, comp, 100K ohms ±10% R: var, comp, 50K ohms ±10% R: fxd, comp, 10K ohms ±10%, 1 W R: fxd, comp, 6800 ohms,±10%, 1W R: var, comp, 50K ohms ±10% R94 R95 R96 0693-1831 2100-0028 2100-0120 R97 R98 2100-0036 2100-0025 R: fxd, comp, 18K ohms ±10%, 2 W R: var, comp, 50K ohms ±10% R: var, ww, 100K ohms tapped at 50K ohms, ±5%, 8 W R: var, comp, lin, 1K ohms R: var, comp, lin, 1.5K ohms ±10% R99 R100 R101 R102 R103, 104 0687-3901 0687-3301 0687-4711 R105 R106 R107 R108 R109 0687-2201 0687-2211 2100-0068 628A-67A R: fxd, comp, 22 ohms ±10%, 1/2 W Not Assigned R: fxd, comp, 220 ohms ±10%, 1/2 W R: var, comp, lin, 500 ohms R: fxd, ww, 200 ohms R110 R111 R112 R113 0687-8231 0687-1051 0687-2731 2100-0034 R: fxd, comp, 82K ohms ±10%, 1/2 w R: fxd, comp, 1M ±10%, 1/2 W R: fxd, comp, 27K ohms ±10%, 1/2 W R: var, comp, lin, 250K ohms ±10% 628A-67A R: fxd, comp, 39 ohms ±10%, 1/2 W R: fxd, comp, 33 ohms ±10%, 1/2 W R: fxd, comp, 470 ohms ±10%, 1/2 W Not Assigned R: fxd, ww, 200 ohms # See introduction to this section 6-6 Note TM 11-6625-2910-14 Section VI Model 626A Table 6-1. Reference Designation Index (Cont’d) Circuit Reference HP Stock No. Description # R: fxd, comp, 1M ±10%, 1/2 W R: var, 1M ±20%, 2 W Not Assigned R: fxd, dep c, 7. 5M ±10%, 1 W R: fxd, dep c, 2.84M ±10%, 1/2 W R114 R115 R116 R117 R118 0687-1051 2100-0047 R119 R120 R121 R122 R123 0770-0002 0770-0003 0727-0292 0727-0281 R: fxd, mfgl, 2.4 ohms ±5%, 4 W R: fxd, mfgl, 3.3 ohms ±5%, 4 W R: fxd, dep c, 3M ±1%, 1/2 W R: fxd, dep c, 1.39M ±1%, 1/2 W Not Assigned R124 R125 R126, 127 R128 R129, 130 0687-4731 0687-1051 0687-3951 0687-1031 0687-1011 R: fxd, comp, 47K ohms ±109%, 1/2 W R: fxd, comp, 1M ±10%, 1/2 W R: fxd, comp, 3.9M ±10% 1/2 W R: fxd, comp, 10K ohms ±10%, 1/2 W R: fxd, comp, 100 ohms ±10%, 1/2 W R131* R132 thru 139 R140, 141 R142 RT1 RT2 thru 101 RT102 RT103 thru 105 RT106 0693-1801 0690-4741 0690-1051 0757-0123 0852-0007 R: fxd, comp, 18 ohms ±10%, 2 W (2 per) R: fxd, comp, 470K ohms ±10%, 1 W R: fxd, comp, 1M ±10%, 1 W R: fxd, met nm, 34.8K ohm, 1%, 1/8 W Tube, ballast, No. 13-4 Not Assigned Thermistor, disc Not Assigned Thermistor, disc 0730-0131 0727-0291 0839-0003 0839-0003 RT107 thru 122 RT123 0839-0022 Not Assigned Thermistor, S1 S2A, B, C, D S3 S4 Switch, Push button Switch, rot: (SYNC SEL.) 2 sect Switch, rot: (MOD, SEL.) 3 sect Switch, micro: SPST, 10 amp S4 Actuator Switch: 4PDT slide Transformer, power Transformer, power S5 T1 T2 3101-1248 3100-0121 3100-0111 3102-0001 3102-0002 3101-1272 9100-0114 9100-0115 # See introduction to this section 6-7 Note TM 11-6625-2910-14 Section VI Model 626A Table 6-1. Reference Designation Index (Cont’d) Circuit Reference HP Stock No. Description # V1 V2 V3 V4 V5 1932-0010 1923-0021 1940-0004 1923-0021 1923-0018 Tube, electron: 6080 Tube, electron: 6AU6 Tube, electron: OA2 Tube, electron: 6AU6 Tube, electron: 6AQ5 V6 V7 V8 V9, 10 V11 1923-0021 1940-0001 1930-0013 1032-0027 1941-0006 Tube, electron: 6AU6 Tube, electron: 5651 Tube, electron: 6AL5 Tube, electron: 12AT7 Tube, electron: 2D21 V12 V13 V14 V15 V16 1930-0013 1932-0027 1941-0005 1932-0027 1930-0016 Tube, electron: GAL5 Tube, electron: 12AT7 Tube, electron: 2D21 Tube, electron: 12AT7 Tube, electron: 6X4 V17 V18 Tube, klystron: (nsr) Part of klystron cavity assembly.) 1932-0002 Tube, electron: 5687 # See introduction to this section 6-8 Note TM 11-6625-2910-14 Section VI Model 626A Table 6-2. Replaceable Parts HP Stock No. Description # Mfr. Mfr. Part No . TQ RS 628A-67A R: fxd, ww, 200 ohms 28480 628A-67A 3 1 0140-0003 0140-0007 0140-0021 0140-0027 0140-0028 C: fxd, mica, 1000pf ±10%, 500 vdcw C: fxd, mica, 680pf ±10%, 500 vdcw C: fxd, mica, 39pf ±10%, 500 vdcw C: fxd, mica, 470pf ±10%, 500 vdcw C: fxd, mica, 560pf ±10%, 500 vdcw 76433 00853 00853 11711 72136 RCM3OB1OZK K1368B10 DR1439B10 CM20B471KN3 CM308561K 2 1 1 1 2 1 1 1 1 1 0140-0031 0140-0032 0140-0035 0140-0041 0140-0071 C: fxd, mica, 220pf ±10%, 500 vdcw C: fxd, mica, 47pf ±10%, 500 vdcw C: fxd, mica, 39pf ±5%, 500 vdcw C: fxd, mica, lOOpf ±10%, 500 vdcw C: fxd, sil mica, 5600pf ±1%, 500 vcw 76433 76433 76433 76433 00656 RCM20B221K RCM2OB470K RCM15E390J RCM15ElOlJ 1464TTMC24345 1 1 1 2 2 1 1 1 1 1 0150-0011 0150-0012 C: fxd, TiO2, 1.5pf ±20%, 500 vdcw C: fxd, cer, 0.1µf ±20%, 1000 vdcw 78488 56289 2 9 1 2 0160-0050 0160-0079 0160-0088 C: fxd, paper, 0.1µf +10%, 400 vdcw C: fxd, paper, 1µf ±10%, 600 vdcw C: fxd, paper, 0.25,µf +10%, 00656 24446 24446 Type GA 29C214A-3-H1038 V161D 23F467 22F21 5 1 1 2 1 1 0160-0089 0160-3192 0180-0019 C: fxd, paper, 2 sect, 0.1 µf/sect, C: fxd, paper, 0.1µf ±20%,1200vdcw C: fxd, elect, 45µf -10% ±50%, 450 vdcw C: fxd, elect, 4 sect., 20;µf/sect, 450 vdcw 00853 01884 14655 obd# LP 104 18M CE41F450R 2 1 5 1 1 2 00853 type PL1 2 1 0490-0009 Relay: time delay, SPST 70563 115NO30T 1 1 0686-1555 0686-3635 0687-1011 0687-1031 0687-1041 R: fxd, comp, 1. 5M ±5%, 1/2 W R: fxd, comp, 36K ohms ±5%, 1/2 W R: fxd, comp, 100 ohms ±109%, 1/2 W R: ixd, comp, 10K ohms ±10%, 1/2 W R: fxd, comp, 100K ohms ±10%, 1/2 W 01121 01121 01121 01121 01121 EB 1555 EB 3635 EB 1011 EB 1031 EB 1041 2 1 4 2 5 1 1 1 1 2 0687-1051 0687-1221 0687-1521 0687-1541 0687-1551 R: fxd, comp, 1M ±10%, 1/2 W R: fxd, comp, 1.2K ohms ±10%, 1/2 w R: fxd, comp, 1.5K ohms ±10%, 1/2 W R: fxd, comp, 150K ohms ±10%, 1/2 W R: fxd, comp, 1.5M ±10%, 1/2 W 01121 01121 01121 01121 01121 EB 1051 EB 1221 EB 1521 EB 1541 EB 1551 5 2 2 2 1 2 1 1 1 1 0180-0125 #See introduction to this section 6-9 TM 11-6625-2910-14 Section VI Model 626A Table 6-2. Replaceable Parts (Cont’d) HP Stock No. Description # Mfr. Mfr. Part No . TQ RS 0687-2201 0687-2211 0687-2241 0687-2251 0687-2731 R: fxd, comp, 22 ohms ±10%, 1/2 W R: fxd, comp, 220 ohms ±10%, 1/2 W R: fxd, comp, 220K ohms ±10%, 1/2 W R: fxd, comp, 2. 2M ±10%, 1/2 W R: fxd, comp, 27K ohms ±10%, 1/2 W 01121 01121 01121 01121 01121 EB 2201 EB 2211 EB 2241 EB 2251 EB 2731 1 1 2 1 1 1 1 1 1 0687-3301 0687-3321 0687-3341 0687-3901 0687-3921 0687-3931 0687-3941 0687-3951 0687-4711 0687-4731 0687-5631 R: fxd, comp, 33 ohms ±10%, 1/2 W R: fxd, comp, 3.3K ohms ±10%, 1/2 W R: fxd, comp, 330K ohms ±10%, 1/2 W R: fxd, comp, 39 ohms ±10%, 1/2 W R: fxd, comp, 3.9K ohms ±10%, 1/2 W R: fxd, comp, 39K ohms ±10%, 1/2 W R: fxd, comp, 390K ohms ±10%, 1/2W R: fxd, comp, 3.9M ±10%, 1/2 W R: fxd, comp, 470 ohms ±10%, 1/2 W R: fxd, comp, 47K ohms ±10%, 1/2 W R: fxd, comp, 56K ohms ±10%, 1/2 W 01121 01121 01121 01121 01121 01121 01121 01121 01121 01121 01121 EB 3301 EB 3321 EB 3341 EB 3901 EB 3921 EB 3931 EB 3941 EB 3951 EB 4711 EB 4731 EB 5631 1 1 1 1 1 1 1 1 1 2 1 1 1 1 1 1 1 1 1 1 1 1 0687-6831 0687-8211 0687-8231 0690-1001 0690-1031 R: fxd, comp, 68K ohms ±10%, 1/2 W R: fxd, comp, 820 ohms ±10%, 1/2 W R: fxd, comp, 82K ohms ±10%, 1/2 W R: £xd, comp, 10 ohms ±10%, 1 W R: fxd, comp, 10K ohms ±10%, 1 W 01121 01121 01121 01121 01121 EB 6831 EB 8211 EB 8231 GB 1001 GB 1031 1 1 1 2 3 1 1 1 1 1 0690-1041 0690-1051 0690-1221 0690-2231 0690-2241 R: fxd, comp, 100K ohms ±10%, 1 W R: fxd, comp, 1M ±10%, 1 W R: fxd, comp, 1.2K ohms ±10%, 1 W R: fxd, comp, 22K ohms ±10%, 1 W R: fxd, comp, 220K ohms ±10%, 1 W 01121 01121 01121 01121 01121 GB 1041 GB 1051 GB 1221 GB 2231 GB 2241 1 6 1 1 2 1 2 1 1 1 0690-3341 0690-4751 0690-4741 0690-5641 0693-1231 R: fxd, comp, 330K ohms ±10%, 1 W R: fxd, comp, 3.9M ±10%, 1 W R: fxd, comp, 470K ohms ±10%, 1 W R: fxd, comp, 560K ohms ±10%, 1 W R: fxd, comp, 12K ohms ±10%, 2 W 01121 01121 01121 01121 01121 GB 3341 GB 4751 GB 4741 GB 5641 HB 1231 1 1 8 1 1 1 1 3 1 1 0693-1531 0693-1541 0693-1831 0693-3331 0693-3341 R: fxd, comp, 15K ohms ±10%, 2 W R: fxd comp, 150K ohms ±10%, 2 W R: fxd comp, 18K ohms ±10%, 2 W R: fxd, comp, 33K ohms ±10%, 2 W R: fxd, comp, 330K ohms ±10%, 2 W 01121 01121 01121 01121 01121 HB 1531 HB 1541 HB 1831 HB 3331 GB 3341 1 1 1 1 1 1 1 1 1 1 #See introduction to this section 6-10 TM 11-6625-2910-14 Section VI Model 626A Table 6-2. Replaceable Parts (Cont’d) HP Stock No. Description # Mfr. Mfr. Part No . TQ RS 1 1 1 0693-6801 0693-6821 0727-0223 R: fxd, comp, 68 ohms ±10%, 2 W R: fxd, comp, 6.8K ohms +10%, 2 W R: fxd, dep c, 216.3K ohms +1%, 01121 01121 19701 HB 6801 HB 6821 DC1/2BR5 obd# 1 1 1 0727-0244 R: fxd, dep c, 500K ohms +10%, 1/2 W 19701 DC1/2AR5 obd# 1 1 0727-0252 R: fxd, dep c, 740K ohms +1%, 1/2 W 19701 DC1/2AR5 obd# 1 1 0727-0253 R: fxd, dep c, 750K ohms +1%, 1/2 W 1/2 W 19701 DC1/2AR5 obd# 1 1 0727-0281 0727-0291 0727-0292 0730-0062 R: fxd, dep c, 1.39M+1%, 1/2W R: fxd, dep c, 2.84M l1%, 1/2 W R: fxd, dep c, 3M +1%, 1/2 W R: fxd, dep c, 80K ohms +1%, 1 W 19701 19701 19701 19701 DC1/2AR5 DC1/2R5 DC1/2CR5 DC1R5 obd# obd# obd# obd# 1 1 1 1 1 1 1 1 0730-0079 0730-0087 0730-0092 0730-0096 0730-0100 R: fxd, dep c, 216.3K ohms +l%, 1W R: fxd, dep c, 370K ohms +L1%, 1 W R: fxd, dep c, 490K ohms +1%, 1 W R fxd, dep c, 683. 7K ohms +1%, 1 W R: fxd, dep c, 800K ohms l1%, 1 W 1S701 19701 19701 19701 19701 DC125 DC1R5 DC1R5 DC125 DC1R5 obd# obd# obd# obd# obd# 1 1 1 1 1 1 1 1 1 1 0730-0110 0730-0131 0770-0002 0770-0003 0770-0004 R: fxd, dep c, 1.63M +1%, 1 W R: fxd, dep c, 7. 5M i1%, 1 W R: fxd, mfg., 2.4 ohms +5%, 4 W R- fxd, mfg., 3.3 ohms +5%, 4 W R: fxd, mfg., 10K ohms +55%, 4 W 19701 19701 07115 07115 07115 DC1R5 DC1R5 type LP1-4 LP1-4 LP1-4 obd# obd# obd# obd# obd# 1 1 1 1 1 1 1 1 1 1 0773-0009 0815-0003 0816-0006 R: fxd, mfg., 66K ohms 45%, 5 W R: fxd, ww, 4K ohms ±5%, 10 W R: fxd, ww, 5K ohms +10%, 10 W 07115 75042 35434 type LP1-5 type 1-3/4A type C-10 obd# 3 1 2 1 1 1 0839-0003 0839-0022 Thermistor, disc Thermistor, 83186 83186 27D1 32A5 04 2 1 2 0 0852-0007 Tube, ballast, No. 13-4 70563 13-4 1 1 1120-0037 Meter, PWR SET 65092 Model 506 1 1 1200-0005 1200-0035 Socket, tube: octal Socket, tube 71785 02660 101-29-11-024 77M1P-11T 4 1 1 1 1250-0074 Connector, female: BNC 91737 UG-290/U 1 1 #See introduction to this section 6-11 TM 11-6625-2910-14 Model 626A Section VI Table 6-2. Replaceable Parts (Cont’d) HP Stock No. Description # Mfr. Mfr. Part No . TQ RS 1250-0075 1251-0006 1251-0007 Connector: BNC panel jack Connector, male: 16 contact Connector, female: 16 contact 91737 02660 02660 UG291/U 26-4100-116P 26-4200-165 3 1 1 1 1 1 1251-0026 Connector, male: octal 02660 86CP11T-041-2 obd# 4 1 1251-0052 Connector, male: 11 pin 02660 86CP11T-041-2 1 1 1901-0029 1910-0016 Diode, Si Diode, Ge 02735 73293 obd# HD2135A 14 1 14 1 1923-0018 1923-0021 1930-0013 1930-0016 1932-0002 Tube, electron: 6AQ5 Tube, electron: 6AU6 Tube, electron: 6AL5 Tube, electron: 6X4 Tube, electron: 5687 82219 82219 33173 33173 33173 obd# obd# obd# obd# obd# 1 3 2 1 1 1 3 2 1 1 1932-0010 1932-0027 1940-0001 1940-0004 1941-0003 Tube, electron: 6080 Tube, electron: 12AT7 Tube, electron: 5651 Tube, electron: OA2 Tube, electron: 5696 86684 00001I 86684 86684 86684 obd# 12AT7 5651 obd# 5696 1 4 1 1 2 1 4 1 1 2 2100-0014 2100-0025 2100-0028 2100-0034 2100-0036 R: var, comp, 200K ohms +20% R: var, comp, lin, 1.5K ohms +10% R: var, comp, 50K ohms ±10% R: var, comp, lin, 250K ohms +109% R: var, comp, lin, 1K ohms 11237 01121 01121 11237 71590 obd# JA1L0405152Z JAZL0485503UC type 35 obd# 2 1 5 2 1 1 1 2 1 1 2100-0045 2100-0047 2100-0068 2100-0096 2100-0098 R: var, comp, 100K ohms ±10% R: var, 1M ±20%, 2 W R: var, comp, lin, 500 ohms R: var, comp, lin, IM ±30%, 1/4 W R: var, comp, lin, 20K ohms +20% 01121 01121 01121 11237 11237 JA1N056S104AA JA1N056S105RZ JA1L048S501UC UPE-70 special UPM-45 1 1 1 3 1 1 1 1 2 1 2100-0120 R: var, ww, 100K ohms tapped at 50K 98734 obd# 1 1 2110-0015 Fuse, cartridge: 2.5 amp, s-b (For 115 V operation) Fuse, cartridge: 1.25 amp, s-b (For 230 V operation) 75915 31302.5 1 10 71400 MDL 1.25 2110-0021 #See introduction to this section 6-12 TM 11-6625-2910-14 Section VI Model 62C6A Table 6-2. Replaceable Parts (Cont’d) HP Stock No. Description # Mfr. Mfr. Part No . TQ RS 2140-0009 Lamp, incd: 6-8V type 47 24455 47 1 1 3100-0111 3100-0121 3101-0030 3102-0001 3102-0002 Switch, rot: (MOD SEL) 3 sect Switch, rot: (SYNC SEL.) 2 sect Switch, tog: SPST Switch, micro SPDT, 10 amp S4 Actuator 76854 76854 04009 91929 91929 68732-F3 68731-F2 82601 BZ-2RS JR 1 1 1 1 1 1 1 1 3140-0010 Motor, fan 73793 G5-CW ER-6667 1 1 3160-0012 Blade, fan 06812 0-5527-5 1 1 7.5ft. 8120-0015 Power cable 70903 KH3981/PH7C/ 1 1 9100-0114 9100-0115 Transformer, power Transformer, power 98734 98734 9018 9017 1 1 1 1 9110-0011 Reactor, filter: 6 h 98734 1009 1 1 9140-0019 9140-0020 9140-0021 9140-0022 Inductor, RF: 200 µh Inductor, RF: 400 µh Inductor, RF: 430 tµh Inductor, RF: 500 µh 99848 99848 99848 99848 1200-15-201 1400-15-401 3430-15-431 150-15-501 2 1 1 1 1 1 1 1 MISCELLANEOUS G-32H Coupler, plastic, control shaft (FM AMP, PHASE MOD SEL) 28480 G-32H 2 1 G-74F G-74G G-74H Knob: ZERO SET, OUTPUT ATTEN Knob: PWR SET, FM AMP, FM PHASE Knob: PULSE RATE, PULSEDELAY, PULSE WIDTH(stake on) Knob: SYNC SELECTOR, MOD SELECTOR 28480 28480 28480 G-74F G-74G G-74H 2 3 3 1 1 1 28480 G-74N 2 1 G-74N 626A-28 Thermistor mount assy 28480 626A-28 1 1 626A-32C Output connector, waveguide 28480 626A-32C 1 1 #See introduction to this section 6-13 TM 11-6625-2910-14 Section VI Model 62C6A Table 6-2. Replaceable Parts (Cont’d) HP Stock No. Description # Mfr. Mfr. Part No . TQ RS 626A-38A 626A-38B-1 626A-38B-2 626A-95A Wrench, spanner Screwdriver Wrench Assembly: Tube Klystron cavity assy complete w/ 28480 28480 28480 28480 626A-38A 626A-38B-1 626A-38B-2 626A-95A 1 1 1 1 1 1 W33M-2 Cap, waveguide, plastic molding 28480 4133-0005 1 1 W34M-1 Plug, waveguide (low dielectric loss) 28480 4054-0003 2 1 1400-0084 Fuseholder 75915 342014 1 1 3150-0002 Air Filter Adhesive water soluble; 16.5 fl. oz can equipped with sprayer applicator. Super Filter Coat Brand 82866 obd# 0 1 626A-65D Printed circuit board, pulse section complete with components 28480 1 626A-65E Printed circuit board, power supply section, complete with components 28480 1 626A-65F Printed circuit board, modulator section, complete with components 28480 1 #See introduction to this section 6-14 1 TM 11-6625-2910-14 APPENDIX A REFERENCES DA Pam 310-4 Index of Technical Publications: Technical Manuals, Technical Bulletins, Supply Manuals (Types 7, 8, and 9), Supply Bulletins, and lubrication Work Orders. DA Pam 310-7 Index of Modification Work Orders. TB 9-6625-776-50 Calibration Procedures for Generator, Signal AN, USM-47. TM 11-6625-2910-14-HR Hand Receipt Manual Covering End Item/Components of End Item (COEI), Basic Issue Items (BII), and Additional Authorization List (AAL) for Signal Generator AN/USM-47 (NSN 662500-445-6917). (To be published.) TM 11-6625-2910-24P Organizational, Direct Support and General Support Maintenance Repair Parts and Special Tools Lists for Signal Generator AN/USM-47 (HP626A) (NSN 6625-00-445-6917). TM 38750 The Army Maintenance Management System (TAMMS). TM 740-90-1 Administrative Storage of Equipment. TM 750-244-2 Procedures for Destruction of Electronics Materiel to Prevent Enemy Use (Electronics Command). Change 1 A-1/(A-2 blank) TM 11-6625-2910-14 APPENDIX B COMPONENTS OF END ITEM LIST SECTION I. INTRODUCTION B-1. Scope This appendix lists integral components of and basic issue items for the AN/USM-47 to help you inventory items required for safe and efficient operation. (1) Figure number. Indicates the figure number of the illustration on which the item is shown. (2) Item number. The number used to identify item called out in the illustration. b. National Stock Number. Indicates the National stock number assigned to the item and which will be used for requisitioning. c. Description. Indicates the Federal item name and, if required, a minimum description to identify the item. The part number indicates the primary number used by the manufacturer, which controls the design and characteristics of the item by means of its engineering drawings, specifications, standards, and inspection requirements to identify an item or range of items. Following the part number, the Federal Supply Code for Manufacturers (FSCM) is shown in parentheses. d. Locations. The physical location of each item listed is given in this column. The lists are designed to inventory all items in one area of the major item before moving on to an adjacent area.B-1 before moving on to an adjacent area. e. Usable on Code. Not applicable. f. Quantity Required (Qty Reqd). This column lists the quantity of each item required for a g. Quantity. This column is left blank for use during an inventory. Under the Rcvd column, list the quantity you actually receive on your major item. The Date columns are for your use when you inventory the major item. 5-2. General This Components of End Item List is divided into the following sections: a. Section II. Integral Components of the End Item. These items, when assembled, comprise the NA/USM-47 in operation, to operate it, and to transferred or turned in. The illustrations will help transferred or turned identify these illustrations will help b. Section III. Basic Issue Items. These are the minimum essential items required to place the AN/USM-47 in operation, to operate it, and to AperforN/USM-47 in operation, to operate it, and to perform emergency repairs. Although shipped separately packed they must accompany the AN/USM-47 during operation and whenever it is transferred between accountable officers. The illustrations will assist you with hard-to-identify items. This manual is your authority to requisition replacement BII, based on TOE/MTOE authorization of the end item B-3. Explanation of Columns a Illustration. This column is divided as follows: (Next printed page is B-2) B-1 TM 11-6625-2910-14 SECTION II. INTEGRAL COMPONENTS OF END ITEM (1) ILLUSTRATION (A) (B) FIG. ITEM 1-1 (2) NATIONAL STOCK NUMBER 6625-00-445-6917 (3) DESCRIPTION PART NUMBER (4) LOCATION FSCM SIGNAL GENERATOR AN/USM-47 (HP626A) (28480) B-2 (5) USUABLE ON CODE (6) QTY REQD (7) QUANTITY RCVD DATE TM 11-6625-2910-14 SECTION III. BASIC ISSUE ITEMS (1) ILLUSTRATION (A) (B) FIG. ITEM (2) NATIONAL STOCK NUMBER (3) DESCRIPTION PART NUMBER (4) LOCATION CAGE 3-1 5920-00-280-3178 FUSE, CARMTDG (FOR 115Y), 2.5 AMPS 31302.5 (75915) 3-1 5920-00-131-9817 FSE, CARTRIDG (FOR 230Y), 1.25 AMPS MDL 1.25 (71400) DRSEL-MA Form 6010, (1 Mar 77) (5) USUABLE ON CODE (Edition of 1 Jun 76 is obsolete) B-3/B-4 (6) QTY REQD (7) QUANTITY RCVD DATE 1 1 HISA-FM 545-77 TM 11-6625-2910-14 Appendix D Model 626A APPENDIX D MAINTENANCE ALLOCATION SECTION I. INTRODUCTION h. Replace. The act of substituting a serviceable like type part, subassembly, or module (component or assembly) for an unserviceable counterpart. i. Repair. The application of maintenance services (inspect, test, service, adjust, align, calibrate, replace) or other maintenance actions (welding, grinding, riveting, straightening, facing, remachining, or resurfacing) to restore serviceability to an item by correcting specific damage, fault, malfunction, or failure in a part, subassembly, module (component or assembly), end item, or system. j. Overhaul. That maintenance effort (service/action) necessary to restore an item to a completely serviceable/operational condition as prescribed by maintenance standards (i.e., DMWR) in appropriate technical publications. Overhaul is normally the highest degree of maintenance performed by the Army. Overhaul does not normally return an item to like new condition. k. Rebuild. Consists of those services/actions necessary for the restoration of unserviceable equipment to a like new condition in accordance with original manufacturing standards. Rebuild is the highest degree of material maintenance applied to Army equipment. The rebuild operation includes the act of returning to zero those age measurements (hours, miles, etc.) considered in classifying Army equipments/components. D-1. General. This appendix provides a summary of the maintenance operations for Signal Generator AN/USM-47. It authorizes categories of maintenance for specific maintenance functions on repairable items and components and the tools and equipment required to perform each function. This appendix may be used as an aid in planning maintenance operations. D-2. Maintenance Function. Maintenance functions will be limited to and defined as follows: a. Inspect. To determine the serviceability of an item by comparing its physical, mechanical, and/or electrical characteristics with established standards through examination. b. Test. To verify serviceability and to detect incipient failure by measuring the mechanical or electrical characteristics of an item and comparing those characteristics with prescribed standards. c. Service. Operations required periodically to keep an item in proper operating condition, i.e., to clean (decontaminate), to preserve, to drain, to paint, or to replenish fuel, lubricants, hydraulic fluids, or compressed air supplies. d. Adjust. To maintain, within prescribed limits, by bringing into proper or exact position, or by setting the operating characteristics to the specified parameters. e. Align. To adjust specified variable elements of an item to bring about optimum or desired performance. f. Calibrate. To determine and cause corrections to be made or to be adjusted on instruments or test measuring and diagnostic equipments used in precision measurement. Consists of comparisons of two instruments, one of which is a certified standard of known accuracy, to detect and adjust any discrepancy in the accuracy of the instrument being compared. g. Install. The act of emplacing, seating, or fixing into position an item, part, module (component or assembly) in a manner to allow the proper functioning of the equipment or system. D-3. Column Entries. a. Column 1, Group Number. Column 1 lists group numbers, the purpose of which is to identify components, assemblies, subassemblies, and modules with the next higher assembly. b. Column 2, Component/Assembly. Column 2 contains the noun names of components, assemblies, subassemblies, and modules for which maintenance is authorized. c. Column 3, Maintenance Functions. Column 3 lists the functions to be performed on the item listed in column 2. When items are listed without maintenance functions, it is solely for purpose of having the group numbers in the MAC and RPSTL coincide. D-1 TM 11-6625-2910-14 Appendix D Model 626A d. Column 4, Maintenance Category. Column 4 specifies, by the listing of a "work time" figure in the appropriate subcolumn(s), the lowest level of maintenance authorized to perform the function listed in column 3. This figure represents the active time required to perform that maintenance function at the indicated category of maintenance. If the number or complexity of the tasks within the listed maintenance function vary at different maintenance categories, appropriate "work time" figures will be shown for each category. The number of task-hours specified by the "work time" figure represents the average time required to restore an item (assembly, subassembly, component, module, end item or system) to a serviceable condition under typical field operating conditions. This time includes preparation time, troubleshooting time, and quality assurance/ quality control time in addition to the time required to perform the specific tasks identified for the maintenance functions authorized in the maintenance allocation chart. Subcolumns of column 4-are as follows: C-Operator/Crew O-Organizational F-Direct Support H-General Support D-Depot e. Column 5, Tools and Equipment. Column 5 specifies by code, those common tool sets (not individual tools) and special tools, test, and support equipment required to perform the designated function. f. Column 6, Remarks. Column 6 contains an alphabetic code which leads to the remark in section IV, Remarks, which is pertinent to the item opposite the particular code. D-4. Tool and Test Equipment Requirements (section III). a. Tool and Test Equipment Reference Code. The numbers in this column coincide with the numbers used in the tools and equipment column of the MAC. The numbers indicate the applicable tool or test equipment for the maintenance functions. b. Maintenance Category. The codes in this column indicate the maintenance category allocated the tool or test equipment. c. Nomenclature. This column lists the noun name and nomenclature of the tools and test equipment required to perform the maintenance functions. d. National/NATO Stock Number. This column lists the National/NATO stock number of the specific tool or test equipment. e. Tool Number. This column lists the manufacturer’s part number of the tool followed by the Federal Supply Code for manufacturers (5-digit) in parentheses. D-5. Remarks. a. Reference Code. This code refers to the appropriate item in section II, column 6. b. Remarks. This column provides the required explanatory information necessary to clarify items appearing in section II. TM 11-6625-2910-14 Appendix D Model 626A SECTION II. MAINTENANCE ALLOCATION CHART FOR SIGNAL GENRATOR AN/USM-47 (1) (2) (3) (4) (5) (6) Group number Component/assembly Maint. function Maint. category C O F H D Tool/ equipment Remarks 00 01 SIGNAL GENERATOR, AR/US47 (HP 626A) Inspect Test Service Adjust 0.3 Install Replace Repair Overhaul 0.3 0.3 0.5 0.5 7.0 CIRCUIT CARD ASSMBLY, PLSE SECTION, A1 2.5 Inspect Replace Repair 02 03 04 CIRCUIT CARD ASSEMBLY, POWER REGULATOR, A2 Inspect Replace Repair 0.3 CIRCUIT CARDI ASSEMBLY, NODULATOR, A3Inspect Replace Repair 0.3 0.75 1.5 KLYSTROR ASSEBLY, A4 0.3 0.5 0.5 Inspect Test Replace Repair D-3 1 thru 14 1 1 thru 14 1 1 1 24.0 1 thru 14 0.3 0.5 0.5 1 1 0.5 0.5 1 1 1 1 1 thru 14 A TM 11-6625-2910-14 Appendix D Model 626A SECTION III. TOOL AND TEST EQUIPMENT REQUIREMENTS FOR SIGNAL GENERATOR USM-47 (1) (2 ) TOOL OR TEST EQUIPMENT MAINTENANCE REF CODE LEVEL (3) (4) (5) NOMENCLATURE NATIONAL/NATO STOCK NUMBER TOOL NUMBER 1 H, D TOOL KIT, ELECTRONIC EQUIPMEUT T105/G 5180-o0o-81T7 2 H, D MULTIMETER AN/USM-223A 6625-00-999-7465 3 H, D OSCILLOSCOPE, HEWLETT-PACKARD 160B 6625-00-291-1029 4 H, D AUDIO OSCILLATOR, HEWLETT-PACKARD 200AB 66254)0-519-2384 5 H, D PULSE GENERATOR, HEWLETTPACKARD 212A 6625-00-519-5593 6 H, D VACUUM TUBE VOLTMETER, HEWLETPACKARD 40OU/H 6625-o00-643-1670o 7 H, D VACUUM TUBE VOLTMETER, HEWLETTPACKARD 410B 6625-00-360-2493 B H, D MICROWAVE POWER METER, HEWLETTPACKARD 430C 6625-00-851-4403 9 H, D CRYSTAL DETECTOR, HEWLETTPACKARD M421A 5961-00-86T76990 10 H, D CRYSTAL DETECTOR, HEILE·T-PACKARD P421A 6625-oo-980-9302 11 H, D THERIMSTOR NOUNT, HEWLETTPACKARD M48TB 6625-00-887-7771 12 H, D THERMISTOR KUT, HEWLET-PACKARD P487B 6625-00-618-9192 13 H, D REPUENCY KMEER, HEWLE-PACKARD M532 6625-00-236-8643 14 H, D FREQUENCY METER, HIELETT-PAC KARD P532A 6625-oo-691-6598 DRSEL-MA Form 1 Oct 77 (Edition of 1 Oct 74 may be used until exhausted) D-4 HISA-FM 2132-77 TM 11-6625-2910-14 Appendix D Model 626A SECTION IV. REMARKS REFERENCE CODE A REMARKS RETURN TO HMUFARAUR FOR REPAIR D-5 TM 11-6625-2910-14 Appendix F Model 626A APPENDIX F CODE LIST OF MANUFACTURERS (Sheet 1 of 2) F-1 TM 11-6625-2910-14 APPENDIX F CODE LIST OF MANUFACTURERS (Sheet 2 of 2) F-2 TM 11-6625-2910-14 Appendix F Model 626A WARRANTY CLAIM AND ADJUSTMENT PROCEDURE for microwave tubes supplied by the HEWLETT-PACKARD COMPANY for use in Hewlett-Packard instruments The procedure described below is for use within the United States. For warranty claims arising outside the U.S.A., before returning the tube, fill out the form on the reverse side and send it with a request for shipping instructions to your nearest Hewlett-Packard Sales and Service Office or to: (in Western Europe) Hewlett-Packard S.A. 1217 Meyrin Geneva, Switzerland Telephone: (022) 41 54 00 Telex: 2.24.86 Cable: HEWPACKSA Cable: HEWPACK (Rest of World) Hewlett-Packard Co. International Marketing Dept. 1501 Page Mill Road Palo Alto, California, 94304, U.S.A. Telephone: (415) 326-7000 Telex: 033811 Microwave tubes supplied by the Hewlett-Packard Company, either as original or replacement, for use in Hewlett-Packard instruments are actually warranted by the tube manufacturer and not by Hewlett-Packard. However, all warranty claims on tubes obtained from us either as original or replacement will be processed by Hewlett-Packard. In the event of failure you should purchase a new tube and return your old tube immediately to Hewlett-Packard. Credit allowances will be passed on to you upon receipt of the defective tube. For your convenience, warranty claims for all microwave tubes supplied by the Hewlett-Packard Company may be made on this single form; merely fill out the information on the reverse side and return this form, along with the defective tube, to your HewlettPackard Sales and Service Office or to Hewlett-Packard. Please be sure each space on the form is filled in--lack of complete information may delay processing of your claim. Each tube manufacturer has his own warranty policy. Copies of individual Conditions of Warranty are available from your Hewlett-Packard Sales and Service Office or from the Hewlett-Packard Company. SHIPPING INSTRUCTIONS The following instructions are included to aid you in preventing damage in transit. Package your tube carefully-- no allowance can be made on broken tubes. 1. Carefully wrap tube in 1/4-inch thick cellulosic cushioning, cotton batting, or other soft padding material. Cable assemblies and other accessories not rigidly mounted to the tube should be padded and wrapped separately to prevent damage to the tube during shipment. 2. Wrap the above in heavy kraft paper. 3. Pack in a rigid container which is at least 4 inches larger than the tube in each dimension. 4. Surround the tube with at least 2 inches of shock absorbing material. Be certain that the packing is tight all around the tube. 5. Tubes returned from outside the continental United States should be packed in a wooden box. 6. Mark container FRAGILE and ship prepaid via Air freight or Railway Express. Do not ship via Parcel Post or Air Parcel Post since experience has shown that fragile items are more apt to be damaged when shipped by these means. Note Tubes with permanent magnets can interfere with magnetic compasses. For air shipment plainly mark container: ’-MAGNETIZED MATERIAL" In warranty tubes purchased from Hewlett-Packard may be returned, with a completed warranty Claim Form, to your local Hewlett-Packard Sales and Service Office, or to: Hewlett-Packard Company Customer Service Center 333 Logue Avenue Mountain View, California 94040 USA Rev 12/16/69 TM 11-6625-2910-14 Appendix F Model 626A 12/16/69 TM 11-6625-2910-14 Backdating Appendix Model 626A APPENDIX G BACKDATING MODEL 626A Serial Prefix Serials 176 & below Serials 201 & below Serials 261 & below 003- Make Changes A thru Q B thru Q C thru Q D thru Q Serial Prefix 609651651-01561 to 651-01400 651-01401 to 651-01460 Make Changes I thru Q J thru Q K thru Q L thru Q Serial Prefix 019134229250Serial Prefix 976-01461 to 976-01470 976-01471 to 976-01480 976-01481 to 976-01520 1101A 1202A Make Changes E thru Q F thru Q G thru Q H thru Q Make Changes M thru Q N thru Q 0, P, Q P, Q Q CHANGE A Change paragraph 2-2, page 2-1, to read as follows: Normally, the Model 626A is shipped from the factory with the power transformers (T1 and T2) wired for 115V 50/60 cycle power line operation. The instrument may be easily converted, how- ever, to operate from a 230V 50/60 cycle power line source by changing the wiring of the primary windings from a parallel to a series arrangement, as shown in the schematic. The conversion procedure is as follows: 1. On T1 and T2, remove the bare wire jumpers between terminals 2A and 5A, and terminals 1A and 4A. 2. Connect new jumpers between terminals 4A and 5A, on T1 and T2. 3. Replace the 2. 5-ampere Slo-Blo line fuse for use with 115-volt power with a 1. 25-ampere SloBlo fuse. Change R74 from 18, 000 ohms to: resistor, fixed, composition, 12, 000 ohms, ±10%, 2 W; -hp- Stock No. 25-23K; Mfr., B, HB 1231. Change R74 on the schematic to read 12K. CHANGE B Page 2 make the following changes: V17 heater wire to FL3 should be yellow V17 heater-cathode wire to FL4 should be white Change Modulator and RF Generator Schematic as follows: Voltage on P7 pin 3 should be -650V Add the following information on page 4-11 an paragraph 4-9: -CAUTIONBefore removing the klystron, of the klystron cavity and frequency drive mechanism, you must withdraw the PWR. SET, attenuator from the klystron cavity. Failure to do this will result in a broken power set attenuator. The following steps should be followed to protect the power set attenuator when changing the klystron: G-1 TM 11-6625-2910-14 Backdating Appendix Model 626A CHANGE B Continued 1. Rotate the PWR. SET control maximum clockwise. 2. In Figure 4-8, locate the POWER SET ATTEN. DRIVE in the upper left hand corner of the picture. Loosen the Allen set screws that hold the large gear in the attenuator drive. 3. Locate the collar on the attenuator drive shaft (parallel with the panel) and gently pull this collar away from the large attenuator drive gear until it stops. The power set attenuator card will now be clear of the klystron cavity and you may proceed with the klystron removal. 4. After the klystron assembly has been installed, slide the attenuator shaft back toward the large drive gear making sure the set screw on the collar is on top. 5. With the PWR. SET knob maximum clockwise, press the large gear and collar together with your fingers and tighten the set screws on the gear. 6. Check the operation of the PWR. SET control to make sure it operates smoothly. CHANGE C Parts List: Change S1 to switch, toggle HP 310-11. Change R117 to resistor, fixed 750K +1%, HP 33-750K. Change R118 to resistor, fixed 284K ±1%. HP 33-284K. Change R121 to resistor, fixed 900K, ±+1, HP 31-900K. Change R122 to resistor, fixed 405K, +1%, HP 33-450K. Under miscellaneous change fuseholder to HP 140-16. CHANGE D Parts List: Delete CR2 through CR15. Delete C46 A/B and C47A/B. Delete R142. Delete R132 through R239. Delete R140 and R141. Delete RT1, ballast tube. Change T1 to HP 910-141. Change T2 to HP 910-140. Add C2, C3, C13'and C14; capacitor fixed electrolytic, 45 if., 450 v.d.c.w. Add SR1 and SR2; Rectifier, metallic HP 212-110. Add SR3; Rectifier, metallic HP 212-111. Add SR4; Rectifier, metallic HP 212-111. Add SR5; Rectifier, metallic HP 212-113. CHANGE E Parts List: Delete C48. Change R115 to HP 210-211. Miscellaneous: Mechanical modification in the RF Output connector changes the appearance of the front panel from that shown in the manual. The plastic cover is replaced by a metal captive cap for the flange. G-2 TM 11-6625-2910-14 Backdating Appendix Model 626A CHANGE F Figure 5-18: Change connection on T1 from C3 to C2. Figure 5-18 and Parts List: Change R15 to HP 0730-0100, 800K ohms, i1%, 1W. Change R30 to HP 0727-0244, 516K ohms, +1%, 1/2W. Figure 5-20 and Parts List: Change R41 to HP 0773-0009, 66K ohms, +5%, 5W. Change R52 and R53 to HP 0730-0079, 216.3K ohms, i1%, 1W. Change R64 to HP 0773-0009 66K ohms, i5%, 5W. Change R65 to HP 0690-4751, 4.7 Megohm. Change R79 to HP 0687-4741, 33K ohms, +10%, 1/2W. Figure 5-22 and Parts List: Delete R91 Parts List: Change L3 and L6 to 200ijH, same part number. Change RT123 to HP 0839-0005 thermistor, WE 170575. Table 6-2: Delete reference to HP Part No. 626A-38B. Add Screwdriver, HP Part No. 626A-38B-1, and Wrench Assembly Tube, HP Part No. 626A-38B-2. Change HP Part No. 626A-650D to 626A-65A. Change HP Part No. 626A-65E to 626A-65B. Change HP Part No. 626A-65F to 626A-65C. CHANGE G Figure 5-22 and Parts List: Change C40 to HP 0150-0012, 0. 01f ±20% 1000 v. d. c. w. CHANGE H Table 1-1, Under "Output Range". Change to read, "- - - SWR less than 2. 5 at +lOdBm; 1.2 at OdBm and lower". CHANGE I Figure 5-20 and Parts List: Delete the asterisk (*) adjacent to R41. This was not a factory selected value. CHANGE J Parts List: Change B1 fan motor to HP 3140-0010. G-3 TM 11-6625-2910-14 Backdating Appendix Model 626A CHANGE K Figure 5-18 and Parts List: Change R131 * to HP 0693-6801, 68* ohms, +10%, 2W. CHANGE L Page 2-1, paragraph 2-11: Delete paragraph 2-12 and replace with the following: 2-12. To operate the Model 626A from a 230-volt +10% source, change the primary windings of T1 and T2 from a parallel to a series arrangement. Refer to the schematic diagram and proceed as follows: a. Remove the two bare wire jumpers from the terminals on T1 and T2. These jumpers connect terminal Al to A4 and A2 to A5 on the primary winding. b. Connect a new jumper between terminal A4 and A5. c. Change the line fuse to a 1.25 amp slow-blow. G-4 TM 11-6625-2910-14 Backdating Appendix Model 626A CHANGE L Continued Page 5-23, Figure 5-18: Replace existing figure 5-18 with figure 5-18 below: G-5 TM 11-6625-2910-14 Backdating Appendix Model 626A CHANGE L Continued Parts List: Delete DS1, glow lamp, HP Part No. 2140-0244. Add I1, Lamp, incd: 6-8v. type 47, HP 2140-0009. Delete J1 connector: AC receptacle, 3 pin male, HP Part No. 1251-2357. Delete R142, R: Fxd, met. flm., 34. 8K ohm, 1%, 1/2W, HP Part No. 9757-0123. Delete S5, switch: slide 4PDT, HP Part No. 3101-1272. Change P1, Power Cable to HP 8120-0015. The power cord is not detachable. Change S1, Push-button switch to HP 3101-0030. Switch, toggle SPST CHANGE M Page 6-8, Table 6-1: Change V11 HP Stock No. and Description to 1941-0003 Tube, electron: 5696. Page 6-7, Table 6-1: Delete R126, R127, the HP Stock No. and Description. Page 6-5, Table 6-1: Change R54 HP Stock No. and Description to 0687-4731 R: Fxd. comp. 47K ohm 10%, 1/2W. Page 6-2, Table 6-1: Change C26 and C30 HP Stock No. and Description to 0140-0003 C: Fxd. Mica 10OOpf 10%, 500 udc W. Page 5-25, Figure 5-20: Change V11 description to 5696. Delete R126, R127. Change R54 description to 47K. Change C26 and C30 description to 10O0pf. CHANGE N Page 6-8, Table 6-1: Change V14 HP Stock No. and Description to 1941-0003 tube, electron: 5696. Page 6-7, Table 6-1: Add R126, 127 0687-3951 R: Fxd., comp. 3.9M i10%, 1/2W. Page 6-5, Table 6-1: Change R54 HP Stock No. and Description to 0687-1051 R: Fxd., comp. 1 MEG ohm, 10%, 1/2W. Page 6-5, Table 6-1: Add R59 & R67 HP Stock No. and Description 0687-1041 R: Fxd. comp. 100K ohm 10%, 1/2W. Page 5-25, Figure 5-20: Change V14 description to 5696. Show R127 3. 9M resistor connected between V14 pins 5, 7 and the junction of R63 and C48. Show R126 3. 9M resistor connected between V11 pin 5, 7 and the junction of R57 and R60. Change R54 description to 1M. Show R59 1OOK resistor connected between the -300V buss line and V11 pins 5, 7. Show R67 100K resistor connected between the -300V buss line and V14 pins 5, 7. Show no connection from V14 pin 2 and pin 5, 7 Show no connection from V11 pin 2 and pin 5, 7 G-6 TM 11-6625-2910-14 Backdating Appendix Model 626A CHANGE O Change all references in manual, pertaining to Sync Out Pulse Delay, from "5 to 300 microseconds" to "3 to 300 microseconds". Table 1-1, Sync Out Signal, change to read, "- - - variable 3 to 300 microseconds". CHANGE P Parts List and Illustrated Parts Identification: These instruments manufactured with Blue-Gray Panel and Cabinet parts only. CHANGE Q Parts List Change C35 from HP 0160-3192, 0. l1f. 1200v., to HP 0160-0050, 0. µf, 400v. G-7/G-8 TM 11-6625-2910-14 APPENDIX H M A N U A L CHANGES MANUAL IDENTIFICATION Model Number: 626A Date Printed: March, 1972 Part Number: 00626-90005 This supplement contains important information for correcting manual errors and for adapting the manual to instruments containing improvements made after the printing of the manual. To use this supplement: Make all ERRATA corrections Make all appropriate serial number related changes indicated In the tables below. Serial Prefix or Number 1210A01731 to 01800 1308A01801 to 01850 1308A01851 to 01920 Make Manual Changes 1 1, 2 1-3 Serial Prefix or Number Make Manual Changes 1410A 1542A 41607A 1-4 1-5 1- 4NEW ITEM ERRATA Page 5-19, paragraph 5-57: In step d, change "< 3 microseconds" to "< 5 microseconds". 4Page 5-23, Figure 5-18: Delete C43. Page 5-25, Figure 5-20: Change R54 to 47K and R58 to 100K. Delete R127.IPage 6-3, Table 6-1: 4Page 6-8, Table 6-1: Delete C43. 4Page 6-13, Table 6-1: Change HP stock number for V9 and V10 to 1932-0027. 4Page 6-13, Table 6-2: Change 3101-0030 to 3101-1248 Switch, Push-button. NOTE Manual change supplements are revised as often as necessary to keep manuals u current and accurate as possible. Hewlett-Packard recommends that you periodically request the latest edition of this supplement. Free copies are available from all HP offices. When requesting copies quote the manual identification information from your supplement, or the model number and print date from the title page of the manual 11 June 1976 4 Pages HEWLETT PACKARD Printed in U.S.A. H-1 TM 11-6625-2910-14 00626-90005 Model 626A ERRATA (Contd.) Page 6-14, Table 6-2: 4Change 626A-95A to 00626-6003. Delete 1400-0084 Fuseholder, and add the following Items In its place. 1400-0090 Washer, neoprene 2110-0465 Cap, fuseholder 2110-0467 Nut, hex 2110-0470 Fluseholder NOTE If any part of the old fuseholder (1400-0084) needs replacing all four parts of the new fuseholder must be ordered The old fuseholder can be identified by a straight solder lug to which the white-black-gray wire attaches. On the new fuseholder the solder lug is at a right angle to the body. Add 7120-4162 Label, warning, large (3 each) "HAZARDOUS VOLTAGE" (Large). Add 7120-4163 Label, warning, small (2 each) "HAZARDOUS VOLTAGE" (Small). Add 7120-4295 Label, warning "HAZARDOUS VOLTAGE ALWAYS PRESENT...." Add 7120-5087 Label, warning "TO PREVENT ELECTRICAL SHOCK ...." Illustrated Parts Identification, page 15: Change item 1 to 2680-0129 Screw, Machine 10-32 0.312 Inch long, pan head, Pozidriv. Change item 2 to 2680-0211 Screw, Machine 10-32 0.312 inch long, Flat head, Pozidriv. CHANGE 1 Page 4-3, Figure 4-5: Change R43 to 1.23M. Page 5-25, Figure 5-20: Change R43 to 1.23M. Page 6-5, Table 6-1: Change R43 to 0730-0108 R:FXD, DEP C, 1.23M 1% 1W, 28480, 0730-0108. Page 6-11, Table 6-2: Delete 0730-0110. Add 0730-0108 R:FXD, DEP C, 1.23M 1% 1W, 28480, 0730-0108. CHANGE 2 Page 6-2, Table 6-1: Change C36 to 0160-0595, C: FXD PAPER 0.25 UF · ±10% 1500 VDCW. Page 6-3, Table 6-1: Change C39 to 0160-0593, C:FXD PAPER, 1UF ±10% 600 VDCW. Page 6-9, Table 6-2: Delete 0160-0079 and 0160-0088. Add: 0160-0593, C:FXD PAPER 1 UF + 10% 600 VDCW, 56289, P34315. 0160-0595, C:FXD PAPER 0.25 UF: 10% 1500 VDCW, 56289, P52789. NOTES 1. When 0160-0593 fist replaces 0160-0079, a new mounting bracket, HP Part Number 1400-0512, must also be ordered 2. When 0160-0595 first replaces 0160-0088, a new mounting bracket, HP Part Number 1400-0525 must also be ordered H-2 HEWLETT PACKARD TM 11-6625-2910-14 00626-90005 Model 626A CHANGE 3 Page 4-5, Figure 4-9: Change R69 to 75K Page 5-25, Figure 5-20: Change R69 to 75K. Page 6-5, Table 6-1: Change R69 to 0686-7535, R:FXD COMP 75K OHM 5% 1/2W. Page 6-9, Table 6-2: Add 0686-7535, R:FXD COMP 75K OHM 5% 1/2W, 01121, EB 7525, 1, 1. Page 6-10, Table 6-2: Delete 0687-5631. CHANGE 4 Page 4-9, Figure 4-15: Change R98 to 2500 ohms. Page 5-27, Figure 5-22: Change R98 to 2500 ohms. Page 6-6, Table 6-1: Change R98 to 2100-0207, R: VAR, CONT, 2.5K OHM 20% MC. Page 6-12, Table 6-2: Delete 2100-0025. Add 2100-0207, R: VAR, CONT, 2.6K OHM, 20% MC. CHANGE 5 Page 5-23, Figure 5-18: Change line switch as shown in the following Illustration. Page 6-7, Table 6-1: Change S1 to 3101-1395 SWITCH-PB DPDT-DB ALTNG 10.5A 250 VAC Page 6-13, Table 6-2: Change 3101-1248 (see Errata) to 3101-1395 SWITCH-PB DPDT-DB ALTO H-3 HEWLETT/PACKARD TM 11-6625-2910-14 00626-90005 Model 626A CHANGE 6 Page 5-25, Figure 5-20: Change C25 to 100pF. Change R54 to 100kL. Change t58 to 47k’1. Page 6-2, Table 6-1: Change C25 to 0140-0041 C: fxd, mica 100pF 5% 500 wvdc. Page 6-5, Table 6-1: Change R54 to 0687-1041 R: fxd comp 100k ohm 10% 1/2w. Change R58 to 0687-4731 R: fxd comp 47k ohm 10% 1/2w. H-4 APPENDIX I TM 11-6625-2910-14 ILLUSTRATED PARTS IDENTIFICATION MODEL 626A SUPER HIGH FREQUENCY SIGNAL GENERATOR Copyright HEWLETT-PACKARD COMPANY 1965 1501 PAGE MILL ROAD. PALO ALTO, CALIFORNIA, U.S A. PRINTED: JAN 1965 I-1 TM 11-6625-2910-14 Model 626A Page I-2 REF. 1 2 3 4 5 6 7 8 9 STOCK NO. DESCRIPTION See Figures 8 and 9 See Figure 5 See Figure 8 See Figure 8 See Figure 4 See Figure 6 See Figures 2 and 3 See Figure 7 See Figure 10 QTY. REF. STOCK NO. DESCRIPTION I-2 QTY. REF. STOCK NO. DESCRIPTION QTY. TM 11-6625-2910-14 General Arrangement Model 626A Figure 1. -hp-Model 626A, S.H.F. Signal Generator, General Arrangement Page I-3 TM 11-6625-2910-14 Model 626A Page I-4 REF. 1 2 3 4 5 6 7 8 9 10 11 12 13 STOCK NO. 628A-2 2190-0034 2990-0002 2950-0038 2190-0037 3101-0030 2950-0035 0590-0037 2190-0002 J382A-17 3030-001 61B-3AT 0525-0002 14 0900-0016 15 0590-0012 DESCRIPTION Panel: Cabinet Model Washer: Split lock for #10 screw Screw: Truss head ss 10-24 thd 3/8 in. lg Nut: 11/16 in. wide 1/224 thd Washer: Int. lock 0.78 o.d. Switch: Toggle s.p.s.t. Nut: 9/16 in.wide 15/32thd Nut: 13/16 in. wide 11/16-27 thd Washer: Int. lock 61/64 in. o.d. Mount: Gear Screw: Allen dr set 832 thd 3/16 in.Ig Ferrule, Panel handle Screw: Round head ss 3-56 thd 3/8 in. lg O-Ring: 1/2 in.i.d. 11/16 in. o.d. Nut: .60 in. Dia 15/3232 thd QTY. REF. STOCK NO. 1 16 2390-0001 4 17 3050-0032 19 18 19 20 21 5000-0202 618B-3E 0400-0004 8120-0015 1 1 1 22 1400-0084 23 2110-0015 1 24 1450-0004 25 2140-0009 1 1 1 26 4 16 26 0370-0029 27 3050-0117 28 29 30 61B-40D-3 61B-40D-4 2370-0001 31 620A-40B 1 DESCRIPTION Screw: Bind head ss 6-32 thd 1/2 in. lg Washer: 3/8 in. o.d. 0.172 in. o.d. Dial: Blank 1-3/4 in. dia Handle: Panel Grommet: Nylon Cable: R. F. R-G. -58U per ft Fuseholder: Post type 2-5/64 in. lg Fuse: Cartridge 2.5 amp 125 volt Light: Red indicator 1/2 in.dia Lamp: Incandescent clear no.47 6-8v Knob: 1 in.dia, blk 1/4 in.shaft with arrow Washer: 1 in o.d.5/16 in.i.d. Hub: Frequency dial Plate: Frequency dial Screw: Flat head ss 632 thd ¼ in. lg Window: dial QTY. REF. 32 STOCK NO. 33 628A-36A9 2190-0016 3 2 1 34 2950-0001 35 0370-0030 1 36 37 38 628A-3C 1120-0037 2280-0005 39 40 628A-41A 2470-0001 41 2550-0009 42 43 44 61B-40D-2 628A-40A 2200-0010 45 0520-0025 46 0370-0035 47 0370-0028 1 1 1 1 1 3 1 1 1 4 1 1 Page I-4 DESCRIPTION Dial: Frequency Washer: Int lock 1/2 in. o.d. Nut: 1/2 in. wide 3/8-32 thd Knob: 1 in. dia, blk 1/4 in. shaft Bezel: Air filter Meter: 200A dbm Screw: Round head br 4-40 thd 5/8 in.lg Plate: Panel Screw: Bind head br 632 thd 1/4 in.Ig Screw: Bind head ss 832 thd 1/2 in.lg Cover: Freq.dial Dial: Vernier Screw: Round head ss 4-40 thd 3/4 In.Ig. Screw: Round head 256 thd 1/8 in. lg Knob: ¾ in. Dia, blk ¼ in. Shaft Knob: 1 in. dia, blk ¼ in. shaft QTY. 1 8 8 3 1 1 3 1 4 6 1 1 4 3 2 2 TM 11-6625-2910-14 Model 626A General Arrangement Figure 2. -hp- Model 626A, S. H. F. Signal Generator, Control Panel, Front View TM 11-6625-2910-14 Model 626A Page I-6 REF. 1 2 STOCK NO. 00626-60018 00626-60019 2190-0016 3 4 5 1410-0003 5000-0206 6 5020-0233 7 3030-0001 8 2360-0002 9 10 11 1500-0002 1360-0011 5020-0319 12 2360-0007 13 14 628A-41B 2360-0005 15 21900-0007 16 2190-0018 17 DESCRIPTION QTY. REF. Panel: Cabinet Model Panel: Rack Model Washer: Int. lock 1/2 in. o.d. See Operating and Service Manual Bushing: Threaded 3/832 thd 1/2in Ig Washer: Spring 9/16 in. dia Collar: 1/4 in. shaft ½ in. dia Screw: Allen dr set 8-32 thd 3/16 in. 0g Screw: Round head ss 6-32 thd 1/4 in. 4; Yoke: Coupler 1/4in. Strip: 1 Terminal Shaft: 1/4 in. dia 1-3/16 in. Ig Screw: Phillips ss 6-32 thd 1/2 in. lg Insulator: Modulator Screw: Round head ss 632 thd 3/8in. lg Washer: Int. lock for #6 screw Washer: Split lock for #6 screw See Operating and Service Manual 1 18 19 STOCK NO. 1200-0053 1200-0059 15 20 2950-0033 4 21 2950-0001 4 22 23 628A-65C 5020-0238 24 3050-0080 1 25 5020-0341 1 26 5040-0212 1 27 2 1 28 2550-0009 29 30 0590-0035 0590-0036 31 32 33 1210-0006 628A-41C 2200-0005 3 14 13 6 9 34 2190-0004 35 2390-0009 DESCRIPTION Socket: 7 Pin tube printed circuit mtg Socket: 9 Pin tube shield base printed circuit mtg Nut: 1/2 in. wide 3/8-32 thd Nut: 1/2 in. wide 3/8-32 thd Board: Modulator Head: Coupler 3/4 in. dia Washer: Bakelite 1/4 in. dia Shaft: 1/4 in. ss 1-5/8 in. lg Insulator: Coupler 1 in. dia See Operating and Service Manual Screw: Bind head ss 8-32 thd 1/2 in. lg Nut: For locking bushing Bushing: Locking Bracket: Capacitor mtg Board: Pot mtg Screw: Round head ss 4-40 thd 5/16 in. lg Washer: Int lock for #4 screw Screw: Bind head ss 6-32 thd 3/8 in. Ig I-6 QTY. REF. 1 36 37 628A-12C 2190-0005 STOCK NO. 38 2260-0001 39 2420-0003 40 2190-0008 41 42 0360-0016 2550-0007 1 7 11 1 1 43 1 44 45 628A-12D 2190-0009 46 0360-0005 47 48 628A-41D 1 3 1 2 1 49 2 1 51 52 1210-0003 2200-0008 4 53 628A-65C-2 4 2 50 DESCRIPTION Bracket: Right Washer: Ext lock for #4 screw Nut: 1/4 in. wide 4-40 thd ss Nut: 1/4 in. wide 6-32 thd ss Washer: Ext lock for #6 screw Lug: Terminal 3/4 in. lg Screw: Bind head ss 8-32 thd 3/8 in. lg See Operating and Service Manual Bracket: Right Washer: Int. lock for #8 screw Lug: Terminal 11/16 in. lg Insulator: Capacitor See Operating and Service Manual See Operating and Service Manual See Operating and Service Manual Bracket: Capacitor mtg Screw: Round head ss 4-40 thd 7/16 in. lg Board: Thermistor QTY. 1 8 8 4 2 3 1 2 1 1 1 4 1 TM 11-6625-2910-14 Model 626A Control Panel, Rear View Figure 3. -hp- Model A, S.H.F. Signal Generator, control Panel, Rear view TM 11-6625-2910-14 Model 626A Page I-8 REF. 1 STOCK NO. 2360-0018 2 3 3030-0005 4 2190-0007 5 0380-0014 6 7 8 9 10 11 12 13 14 15 3030-0001 628A-36A22 628A-36A5 5020-0389 628A-36A13 2360-0016 628A-36Q21 2420-0001 2990-0002 2190-0011 DESCRIPTION Screw: Round head ss 6-32 thd 1-3/8 in. Lg See Operating and Service Manual Screw: Allen dr set 8-32 thd 1/8 in. lg Washer: Int lock for # 6 screw Spacer: 1-3/16 in. Lg ¼ in. o.d. Screw: Allen dr set 8-32 thd 3/16 in. lg Drive: Coupling QTY. 1 22 23 7 24 1410-0007 1 25 26 0570-0022 3030-0033 1 Screw: Round head ss 6-32 the 1-1/4 in. lg Washer 16 17 18 19 20 5 21 3 1 3 27 1 28 2 1 29 30 Nut; 5/16 in. wide ss 6-32 thd ½ in. lg Screw: Truss head ss 10-24 thd ½ in. lg Washer: Int lock for # 10 screw STOCK NO. 1410-0017 3050-0019 5020-0248 3102-0002 628A-36A30 628A-36A23 J382A-17 3050-0032 Cam: Microswitch Washer: Spring Hub: Cam REF. 1 31 1 32 1 33 628A-36A6 628A-36A28 0380-0018 628A-36A27 628A-36A1 628A-36A29 628A-36A13 DESCRIPTION QTY. REF. Bearing: Ball Washer: ½ in. o.d. Gear: Offset tooth Lever: Switch actuator Shaft 2 1 1 1 34 3050-0014 STOCK NO. 35 36 626A-77A2 1460-0022 37 38 0360-0036 1410-0004 39 3050-0017 40 0510-0052 2 1 41 2470-0001 2 42 1410-0015 1 43 44 1480-0001 628A-36A14 628A-36A14 628A-36A14 628A-36A14 0510-0040 1 Cam: Drive Mount: Gear Washer: 5/16 in. o.d. 0.190 in. i.d. brass Bearing: Ball ½ in. o.d. 3/16 in. i.d. Screw: 3/8 in. lg Screw: Allen dr set 6-32 thd 3/165 in. lg Gear: Stop 1 1 11 Sleeve 1 Spacer: ¼ in. lg ¼ in. o.d. Eccentric 45 2 46 1 Chassis 47 1 Clamp Hub: Cam 48 1 1 49 50 Page I-8 628A-36A14 0510-0005 DESCRIPTION Washer: 3/8 in. o.d. 0.26 in. i.d. bronze Follower: Cam QTY. 1 1 Spring: Tension 1/8 o.d. 1-/1/2 in. lg Lug: Terminal Bearing: Ball 5/8 in. o.d. ¼ in. i.d. Washer: 3/8 in. o.d. 0.26 in. i.d. bronze Ring: Grip for 1/8 in. shaft Screw: Bind head br 6-32 thd ¼ in. lg Bearing: Ball 5/8 in. o.d. ¼ in. i.d. Pin: Cotter ½ in. lg Bushing: Eccentric 2 2 3 3 1 2 2 1 1 Bracket: Cam follower 1 Shaft: Cam 1 Shaft: Cam roller 1 Ring: Grip for 5/16 in. shaft Shaft: Dial 1 1 Ring: Retaining for ¼ in. shaft 1 TM 11-6625-2910-14 Model 626A Frequency Drive Assembly Figure 4. -hp- Model 626A, S. H. F. Signal Generator, Frequency Drive Assembly Page I-9 TM 11-6625-2910-14 Model 626A Page I-10 REF. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 STOCK NO. 2200-0010 626A-77A2 626A-77A 4 0510-0005 3050-0017 2260-0001 2190-0004 626A-77A3 2200-0004 0520-0001 0510-0011 2210-0004 626A-77A5 3030-0026 26A-77C-1 628A-32A3 DESCRIPTION Screw: Round head ss 4-40 thd ¾ in. lg Follower: Cam QTY. REF. 1 17 18 1 19 626A-37A 626A-59A10 3050-0014 STOCK NO. 1 20 3030-0001 1 3 21 22 23 2 24 0570-0022 3050-0010 626A-77E2 2200-0009 2 25 0510-0039 1 2 4 1 26 3030-0033 27 1460-0036 28 626A-77A8 626A-59A9 626A-59A3 3030-0016 Arm: Lever Ring: Retaining for ¼ in. shaft Washer: 3/8 in. o.d. 0.26 in. i.d. bronze Nut: ¼ in. wide 4-40 thd ss Washer: Int. Lock for #4 screw Nut: Elastic Screw: 4-40 thd Screw: 2-56 thd Ring: Retaining Screw: Flat head ss 4-40 thd ½ in. lg Hub: Lever arm Screw: Cap Holder: #2 Load: Coupler 1 29 1 1 1 30 31 2 DESCRIPTION Shaft: Lever arm Plate: Bearing QTY. REF. 1 32 33 0570-0023 0590-0026 STOCK NO. 34 626A-77A7 626A-77A6 0570-0007 1 Washer: 3/8 in. o.d. 0.26 in. i.d. bronze Screw: Allen dr. Set 8-32 thd 3/16 in. lg Screw: 1-72 thd Washer: 5/16 in. o.d.. Holder: Load 2 35 1 2 4 36 37 1 Screw: Round head ss 4-40 thd ½ in. lg Ring: Retaining for ½. in hsg Screw: Allen dr. Set 6-32 thd 3/16 in. lg Spring: Compression 6 turns x 9/32 in. lg Spring: End plate 38 1 39 1 40 626A-77E1 626A-59A1 626A-59A2 3030-0003 2 41 43 626A-77B2 626A-77B3 3030-0028 44 3030-0030 45 626A-77B1 1 42 1 Load: Plunger 1 Plunger Assy 1 Screw: Allen dr cap 6-32 thd ½ in. lg 8 46 Page I-10 DESCRIPTION QTY. Screw: 0-80 thd Nut: 3/32 in. wide 0-80 thd br Pin: Suppressor 2 2 1 Pin: Guide 1 Screw: Fil head br 0-80 thd 3/16 in. lg Load: ¼ wave 1 1 Casting 1 Cap: Tube 1 Screw: Allen dr set cap 6-32 thd 3/8 in. lg Load: ¾ wave 12 1 Holder: #1 1 Screw: Allen dr set cap 6-32 thd ¼ in. lg Screw: Allen dr set cap 6-32 thd 1 in. lg Screw: Lock 1 2 1 See Operating and Service Manual TM 11-6625-2910-14 Model 626A Cavity Assembly Figure 5. -hp- Model 62A, S. H. F. Signal Generator, Cavity Assembly Page I-11 TM 11-6625-2910-14 Model 626A Page I-12 REF. 1 2 3 4 STOCK NO. 3050-0103 628A-32A 4 5000-0206 5 626A-34B1 5020-0233 6 3050-0032 7 8 61B-27 3030-0001 9 626A-32A1 DESCRIPTION Washer: 9/16 in. o.d. ¼ in. i.d. ss Shaft: Pinion QTY. REF. 10 STOCK NO. 2200-0003 1 1 11 3030-0016 WASHER: Spring 9/16 in. lg Tube: Screwdriver 1 12 29550-0001 13 2190-0016 Collar: ¼ in. shaft ½ in. dia Washer: 5/16 in. o.d. 0.190 in. i.d. bras Filter Assembly Screw: Allen dr set 8-32 thd 3/16 in. lg Coupler 1 1 14 15 2210-0004 4 1 16 2 17 626A-32A2 626A-32A3 0510-0053 1 18 2420-0001 DESCRIPTION Screw: Round head ss 4-40 thd ¼ in. lg Screw: Allen head ss 4-40 thd ½ in. lg Nut: ½ in. wide 3/8-32 thd br Washer: Int lock ½ in. o.d. Screw: Flat head ss 4-40 thd ½ in. lg Block: End QTY. REF. 1 19 20 21 626A-27A 626A-28 3030-0013 STOCK NO. 1 22 23 628A-24C 1480-0008 1 24 1 25 26 628A-32A6 626A-37B 3030-0060 27 3030-0007 28 29 626A-71A 628A-24D 8 1 Load: Coupler 1 Ring: Grip for 3/16 in. shaft Nut: 5/16 in. wide ss 6-32 thd w/lock Page I-12 1 4 DESCRIPTION Filter Mount: Thermistor Screw: Allen dr cap 6-32 thd ¾ in. lg Pinion: Power set Pin: 1/16 in. dia ½ in. lg Shaft: Bevel gear Shaft Screw: Allen head set 2-56 thd Screw: Allen dr cap 4-40 thd 1/8 in. lg Coupler: Power set Gear: Bevel QTY. 1 1 4 1 2 1 1 2 2 1 1 TM 11-6625-2910-14 Directional Coupler Assembly Model 626A Figure 6. -hp- Model 626A, S.H. F. Signal Generator, Directional Coupler Assembly Page I-13 TM 11-6625-2910-14 Model 626A Page I-14 REF. STOCK NO. 1 2360-0012 2 2390-0001 3 2360-0008 4 5 1480-0063 626A-34A2 626A-34A14 2360-0008 6 7 8 9 10 11 12 13 14 15 2190-0007 1480-0015 626A-34A16 626A-34A21 1410-0021 626A-34A3 0360-0005 16 626A-34A5 8160-0009 17 1460-0022 18 626A-34A12 2460-0001 19 20 3030-0022 DESCRIPTION Screw: Round head ss 6-32 thd 7/8 in. lg Screw: Bind head ss 6-32 thd ½ in. lg Screw: Round head ss 6-32 thd ½ in. lg Pin: Dowel ¼ in. lg Connector 180° QTY. 21 4 22 STOCK NO. 628A-34A19 3050-0017 27 23 2 25 26 27 628A-34A28 628A-34A6 X382A-5 X382A-4 2370-0007 8 28 0361-0032 8 29 9300-0015 4 30 31 X885-29 2390-0007 12 2 1 Card: Bent Screw: Round head ss 6-32 thd 7/8 in. lg Washer: Int lock for #6 screw Pin: dowel ¼ in. dia 3/8 in lg Adapter REF. 24 2 32 Insert: Attenuator 2 Bearing: Ball 2-1/4 in. o.d. 1.813 i.d. Center: Section 33 4 2 Lug: terminal 11/16 in. lg Cover: Attenuator Braid: R.F. ¼ in. dia alum Spring: Tension 1/8 in. o.d. 1-½ in. lg Card: Center Screw: Phillips br 6-32 thd ¼ in. lg Screw: Allen dr set 6-32 thd 1”8 in. lg 626A-34A16 0900-0008 34 35 3050-0015 8160-0008 4 36 3030-0003 1 37 628A-34A7 5020-0233 A/R 2 38 39 5000-0206 2 40 2 41 628A-34A11 0520-0009 1 42 X382A-18 DESCRIPTION QTY. Bracket: Flag mounting REF. STOCK NO. 43 3030-0021 44 2460-0003 45 0380-0011 46 47 628A-34A29 2420-0003 48 2390-0009 49 0380-0003 50 1 Washer: 3/8 in. o.d. 0.26 i.d. bronze Ring: Retaining 1 4 flag: Assembly Shaft: Flag Spring: Flag Screw: Flat head ss 6-32 thd 1 in. lg Eyelet: Flat fl type .084 o.d. Spring: Braided nylon 45 lb test Window Screw: Bind head ss 6-32 thd 5/16 in. lg Adapter O-Ring: 1.188 i.d. 1.438 o.d. Washer: 5/8 in. o.d. Braid: R.F. ¼ in. dia alum Screw: Allen dr cap 6-32 thd 3/8 in. lg Shaft: Lock Collar: ¼ in. shaft ½ in. dia Washer: Spring 9/16 in. dia Dial: Attenuator 1 1 1 2 2 A/R 1 51 2 52 628A-34A31 626A-34A4 1410-0015 2 53 0510-0005 2 4 54 55 X382A-36 3050-0019 A/R 56 57 J382A-4 5020-0248 1 58 2190-0011 2 59 2920-0003 2 60 61 628A-34A-1 626A-34A17 626A-34A22 626A-34A13 626A-34A23 2 1 Screw: Flat head ss 2-56 thd ¼ in. lg Hub: Dial 62 2 1 63 64 Page I-14 DESCRIPTION Screw: Allen dr set 8-32 thd 3/16 in. lg Screw: Phillips br 6-32 thd 5/16 in. lg Spacer: ¾ in. lg ¼ in. o.d. Shield QTY. 2 2 2 1 Nut: ¼ in. wide 6-32 thd Screw: Bind head ss 6-32 thd 3/8 in. lg Spacer 1/8 in. lg ¼ in. o.d. {Pulley Assembly 2 2 2 1 Housing: Attenuator 1 Bearing: Ball 5/8 in. o.d. ¼ in. i.d. Ring: Retaining for ¼ in. shaft Gear: Stop Washer: Brass ½ in o.d. 2 in. i.d. End: Section Gear: Offset tooth 1.218 in. dia Washer: Int lock for #10 screw Screw: Round head ss-10-24 thd 5/8 in. lg Shaft: Worm Mount: Bearing Choke: End section 2 2 1 4 1 1 1 1 1 2 1 1 Card: End 2 End: Section 2 TM 11-6625-2910-14 Model 626A Attenuator Assembly Figure 7. -hp- Model 626A, S. H. F. Signal Generator, Attenuator Assembly Page I-15 TM 11-6625-2910-14 Model 626A Page I-16 REF. STOCK NO. 1 2990-0001 2 2930-0004 3 2370-0002 4 5 628A-1AL 2900-0002 6 250-0007 7 8 1251-0026 2980-0002 9 10 11 12 628A-12N 628A-12G 1200-0005 1400-0033 13 626A-65E 14 15 16 1400-0032 2420-0001 12550-0075 DESCRIPTION Screw: Truss head ss 10-24 thd 3/8 in. lg Screw: Flat head ss 10-24 thd ½ in. lg Screw: Flat head ss 6-32 thd 3/8 in. lg Gusset: Left Screw: Truss head 10-24 thd ½ in. lg Screw: Bind head ss 8-32 thd 3/8 in. lg Connector: Male 8 pin Nut: 3/8 in. wide 10-24 thd w/lock Bracket Bracket Socket: Octal tube clamp: Tube 1-1/4 in. dia board Assy: Voltage regulator Clamp: Tube 1-5/8 in. dia Nut: 5/16 in. wide ss 6-32 thd w/lock Connector: BNC QTY. REF. STOCK NO. 17 626A-65D 18 1200-0053 19 20 21 22 628A-12F 1200-0035 1200-0008 3050-0100 23 0380-0008 24 2360-0005 25 26 628A-12P 2360-0018 11 3 4 1 1 5 4 1 1 1 4 1 27 28 29 628A-1 628A-65D 2190-0005 1 30 1200-0062 1 31 2260-0001 7 3 32 2190-0004 DESCRIPTION Attenuator Assy: Power set Socket: 7 pin tube printed circuit mtg Bracket Socket: 11 pin tube Socket: 9 pin tube Washer: 7/16 in. o.d. 0.147 i.d. brass Spacer: ½ in. lg ¼ in. o.d. Screw: Round head ss 6-32 thd 3/8 in. lg Bracket Screw: Round head ss 6-32 thd1-1/2 in. lg Chassis Board Assy: Circuit Washer: Ext lock for #4 screw Socket: 9 pin tube mtg printed circuit Nut: ¼ in. wide 4-40 thd ss Washer: Int lock for #4 screw Page I-16 QTY. REF. STOCK NO. 33 0380-0014 34 35 36 3100-0121 628A-12K 3030-0020 37 38 628A-1AR 2190-0016 39 2950-0001 40 41 42 55020-0233 626A-38A 1400-0010 43 1400-0011 44 45 1400-0044 626A-38B1 626A-38B2 1 11 1 1 1 2 2 2 1 2 1 1 2 46 4 2 2 DESCRIPTION Spacer: 1-3/16 in. lg ¼ in. o.d. Switch: Rotary Bracket Screw: Allen dr set 8-32 thd 3/16 in. lg Gusset: Right Washer: Int lock 0.185 in o.d. Nut: ½ in. wide 3/8-32 thd br Collar Wrench: Spanner Clip: Fuse 0.406 in. lg x .375 in w Clip: Fuse 0.438 in. lg x 0.75 in h Clip Screwdriver: QTY. 1 1 1 2 1 1 1 1 1 2 1 1 1 Wrench 1 TM 11-6625-2910-14 Model 626A Chassis, Front View Figure 8. -hp- Model 626A, S.H. F. Signal Generator, Chassis Front View Page I-17 TM 11-6625-2910-14 Model 626A Page I-18 REF. 1 2 3 4 5 6 7 STOCK NO. 628A-1 2190-0034 2740-0002 1400-0031 3050-0002 2740-0003 2420-0001 DESCRIPTION QTY. REF. Chassis Washer: Int lock for #4 screw Nut: 5/16 in. wide 10-32 thd ss Clamp: Cable 3/8 in. dia nylon Washer: 7/16 in. o.d. 0.203 in. i.d. steel Nut: 3/8 in. Wide 10-32 thd w/lock Nut: 5/16 in. Wide ss 6-32 thd w/ lock 1 8 STOCK NO. 7 9 2360-0020 7 1 10 11 12 0360-0012 1200-0005 2360-0005 1 13 2440-0007 1 14 3030-0001 DESCRIPTION See Operating and Service Manual Screw: Round head ss 6-32 thd 2 in. lg Strip: 1 terminal Socket: Octal tube Screw: Round head ss 6-32 thd 3/8 in. lg Screw: round head br 6-32 thd 2-1/2 in. lg Screw: Allen dr set 8-32 thd 3/16 in. lg 4 Page I-18 QTY. 3 1 6 REF. STOCK NO. 15 2360-0013 16 3160-0012 17 0360-00151 18 1520-0001 19 2190-0021 20 2950-0042 2 2 2 DESCRIPTION Screw: Round head ss 6-32 thd 1 in. lg Fan blade: 4 blades 4.5 in. dia Strip: 3 terminal 2 in. 1 gnd Plate: Capacitor mtg 1-17/32 x 2-3/16 in. Washer: Int lock for #4 screw Nut: 1 in. wide ¾-20 thd br QTY. 2 1 1 2 5 5 TM 11-6625-2910-14 Model 626A Chassis, Rear View Figure 9. -hp- Model 626A, S.H. F. Signal Generator, Chassis, Rear View Page 1-19 TM 11-6625-2910-14 Model 626A Page I-20 REF. 1 STOCK NO. 628A-44A DESCRIPTION Dust: Cover QTY. REF. STOCK NO. DESCRIPTION 1 Page I-20 QTY. REF. STOCK NO. DESCRIPTION QTY. TM 11-6625-2910-14 Model 626A Page I-21 Figure 10. -hp-Model 626A, S. H. F. Signal Generator, Cabinet Page I-21/I-22 By Order of the Secretary of the Army: BERNARD W. ROGERS General, United States Army Chief of Staff Official: J. C. PENNINGTON Brigadier General, United States Army The Adjutant General Distribution: Active Army: TSG (1) USAARENBD (1) USAINSCOM (2) TRADOC (2) DARCOM (1) TECOM (2) OS Maj Comd (2) USACC (2) HISA (Ft Monmouth) (26) Armies (1) USASIGS (10) Svc Colleges (1) Fort Huachuca (5) Ft Richardson (CERCOM Ofc) (10) Fort Carson (5) Fort Gillem (10 WSMR (1) USAERDAA (1) ARNG & USAR: None USAERDAW (1) Army Dep (1) except LBAD (10) TOAD (14) SHAD (3) USA Dep (1) Sig Sec USA Dep (1) Units org under fol TOE: (1 cy each unit) 29-134 29-136 32-52 32-57 Units org under fol TOE: (2 cys each unit) 29-207 29-610 For explanation of abbreviations used, see AR 310-50. žUS GOVERNMENT PRINING OFFICE 1984 0- 445-859 PIN: 035306-0000